Document pB08erMz25JwVJo8y4eOxXywB

TRANSVAAL CHAMBER OF MINES. Miners' Phthisis Competition Committee. REPORT OF JUDGES. APRIL, 1904. PLEASE RETURN ----- TO ----- CHAMBER OF MINES LIBRARY. JOHANNESBURG: WALKER A SNABHAU, PRINTERS. * o Messrs. The President and Executive Council of the Transvaal Chamber of Minesy Johannesburg. Gentlemen, The judges appointed to adjudicate upon the suggestions and devices for combating the disease known as Miners' Phthisis, which have been received as a result of vour Chamber's advertisement of the 10th October, 1902, herewith beg to submit their Report and fix the awards in accordance with your instructions,, and the terms of their reference. Chamber's Advertisement. The Transvaal Chamber of Mines caused the following advertisement to be inserted in the papers of the United Kingdom. Europe, Australia, South Africa and America :-- "Transvaal Chamber of Minks. "MINERS' PHTHISIS. " The Chamber is desirous of taking steps to obviate or minimise the occurrence " of this disease, aud invites practical suggestions and plans for combating' the causes " leading to the same. "No definite information is before the Chamber as to the causes of the disease, " but the general assumption is that it is chiefly due to the inhalation of the fine " dust given off during machine drilling operations. " The Chamber offers the following awards for the three bent practical suggestions " and devices on this subject, viz. :-- " 1st Prize ... 500 and Gold Medal. "2nd Prize ... 250. " 3rd Prize ... 100. " In suggesting devices for obtaining the object desired, rhe following points " are to be taken into consideration :-- . " (1) The applicability of the device or apparatus to the existing system of machine drilling. " (2) The practical demonstration of the device or apparatus. "The judges, before making the final award of prizes, will be entitled to require " tests, aud if not satisfied with any of the proposed devices, will be at liberty to " re-open the competition, or to award part only of the prizes. Papers in connection "with this subject must be accompanied by plans, models or apparatus of the devices **suggested! and will be receivable. " (a) At the offices of the Chamber. Johannesburg. Postal Address : Box 809, Johannesburg : up to the 15th February, 1903. " (b) At the London Agents of the Chamber, Messrs. Barsdorf & Go., Wool Exchange, Coleman Street ; up to the 15th January, 1903. " (c) At the Paris Agents of the Chamber, Campagnie Frangaise de Mines d'Or et de L' Afrique du Siul, 20, Rue Taitbout ; up to the 15th of January, 1903. " The judges for the award of the prizes will consist of, " Two Members of the Transvaal Medical Society. ' " Two Members of the Mine Managers' Association of the Witwatersrand. " Two Members of the Mechanical Engineers' Association of the " Witwatersrand. " together with " Three Consulting Mining Engineers to be selected by the Transvaal " Chamber of Mines, " aud, "`Two practical Rock Drill Miners to; be selected by the Mine Managers' " Association. : " The decision of the majority to be final. .' " By order of the Executive Committee, :. A. R. GOLDRING, Johannesburg, October 10th, 1902. Secretary'." 4 Appointment and Names of Judges. The judges were appointed as follows :-- Nominated by the Transvaal Medical Society : Drs. Irvine and Macaulay. Nominated by Mine Managers' Association : Messrs. J. Harry Johns and R. M. Catlin ; with Messrs. Samuel Johns and Hugh Nicholls as practical Rock Drill Miners. Nominated by the Mechanical Engineers' Association : Messrs. W. H. Wood and J. A. Mills. Nominated by the Transvaal Chamber of Mines : Messrs. H. H. Webb, G. E. Webber and Fred Hellmann. Dr. Walter C. C. Pakes was elected a judge at the meeting of the 29th October, 1903. Meetings of Judges. The first meeting of the judges was held on 7th March, 1903, and was opened by the President of the Chamber, Sir George Farrar, who explained more fully the object of the competition which the Chamber had inaugurated, and stated that the Chamber would furnish such clerical assistance as might be required and would defray all expenses incurred. The judges have held in all twelve meetings. Suggestions and Devices Submitted. There were in all 229 competitors whose suggestions and devices were tabulated as follows :-- 1. Respirators and Masks ... ... 2. Dust Extractors and Hoods .. / ... 3. Water Drills ... ... ... 4. Jets delivering water inside the hole ... 5. Jets delivering water at mouth of hole ... 6. Sprays ... ... ... ... 7. Atomisers ... ... ... ... 8. Medical suggestions ... ... ... 9. Miscellaneous ... ... ... ... ... ... ... ... ... ... ... ... 41 35 9 4 60 22 6 15 37 229 Weeding Out. After careful consideration, and having examined every suggestion individually, the judges determined to condemn as quite impracticable and useless classes 1, 2, 8 and 9. The remaining classes, 3, 4, 5, 6 and 7, were reserved for further consideration, and a device typical of each class selected for trial under working conditions. . Jets Inside of Hole. A device of this kind was tested at the Crown Reef in the presence of the judges on the 2nd April, 1903. The jet was quite independent of the drill, and required a man to hold and direct it. The drill blocked at 5ft. 6in. As a result of this test class 4 was rejected, the judges being of opinion that such a device, in addition to its use being entirely optional, would probably cause the drill to block frequently and thus prove troublesome. In addition, the necessity for another hand to hold the jet would mean extra and, it was felt, unnecessary expense. 5 Jets Delivering Water at Mouth of Hole. Such a jet was tried at the Simmer East on the 8th April, 1903, in the presence of the judges. The apparatus was attached to the drill, but when the drill jammed was in the way. The drill stuck repeatedly at about 5ft. 6m. About seventy-five per cent of the dust was settled by the jet, and it did not produce supersaturation of the atmosphere. The judges, however, discarded this class on the ground that water delivered at the mouth of the hole would cause the drill to stick and thus cause the miners to discard it. Sprays. Spraying devices were found to be open to the same objection as jets, and were condemned by the judges. Water Drills. The principle of the water drill was so generally approved that the judges decided to institute exhaustive tests in connection with the drills that had been submitted in order to determine their relative efficiency and likewise their efficiency as compared with the ordinary types of drill in use on these fields. In order to accomplish this end cablegrams were sent to the designers and makers in England to ship out complete drills and appliances at once, the freight out and back to be paid hv the Chamber of Mines. The result was somewhat disappointing for, after much delay, it was found that of the nine who had submitted drawings and specifications covering water drills only two were able actually to enter the competition, namely, the Leyner and the Ingersoll Sargeant. The test run was made at the Crown Reef beginning on the 2nd November, 1908, and ending on the 13th January, 1904. The result of the test is embodied in Mr. Wood's report to the judges, which is appended. It demonstrates clearly that the Leyner drill as a water drill possesses great advantages over the Ingersoll Sargeant water drill in its present state of development. Taken in conjunction with the other evidence before the judges the test also shews the general inefficiency of both drills as compared with the ordinary drills in use on the Rand. That fact, together with the evidence submitted by mine managers as to the high cost of maintenance and the short life of the machines make it quite impossible to recommend these drills in the forms submitted, for general use on these fields. The judges, hqwever, fully recognise the principle embodied in the water drill, namely, that of laying the dust at the very point where it is generated and since the incidence of silicosis falls principally on rock drill * miners in drives and rises, they hope that great improvements in the surroundings of such workers will be achieved by means of water drills when their mechanical arrangements shall have been so improved as to make them practicable in this country. The reports from various mine managers, which are attached, support the views of the judges with regard to this point. In recognition of the principle and of the effort to apply it the judges have awarded the 2nd prize of 250 to the Leyner Drill in the hope that this award may stimulate manufacturers to further exertions in the direction of the production of a perfected water drill. Atomisers. Of the various Atomisers submitted Mr. Thos. J. Britten's is the most perfect mechanically, and therefore the most useful machine. It was found to lay 75 per cent, of the dust in the drive where it was tested (vide Dr. Pakes's report of the 23rd April, 1903), and would therefore probably lay a like percentage during blasting and shovelling. It can be used during drillingand blasting, and also whilst shovelling is being done in drives and stopes. It further possesses the distinct advantage of laying the nitrous fumes contained in the gases after blasting. 6 If a little lime he mixed with the water used, a portion of the carbonic acid resulting from blasting would also be absorbed. It assists local ventilation, and is simple and. cheap in construction. On the other hand it involves a separate mechanism, requiring extra attention, which causes a disinclination on the part of the miners to use it. It is not necessary to the successful running of the drill, and its use, therefore, depends on the good will of the miners. The latter might prefer to discard it rather than bother with it. It involves the necessity of working in a supersaturated atmosphere, which disadvantage, however, is a negligeable quantity if change houses are used by the men. It necessitates absolute!v a supplv of pure water underground for use with the Atomiser, and therefore some system of water supplv in the mine, which would be more or less cost!v. The judges are of opinion that Mr. Britten's Atomiser is the best practical device that has been suggested, and therefore award it the First Brize of 500 and the Gold Medal.' Resolutions. The judges adopted the following resolutions as embodying their opinions and decisions :-- 1. That all devices are considered inapplicable except the Water Drill and the Atomiser. 2. That since the judges have two separate devices before them, one of which has proved practicable and the other of which has a very great theoretical value (although no absolutely practical device has been submitted) two prizes be awarded--viz., to the Atomiser and to the Water Drill. 3. That the judges award the full amount of the First Brize and the Gold Medal to the Atomiser, which has been demonstrated as being, in the terms of the reference, `* the best practical ' suggestion ' submitted." 4. That, in the opinion of the judges, the best means of combating the disease would be the use in drilling of a perfect Water Drill, together with the use of an Atomiser for allaving the dust and gases during blasting and shovelling, o. That the full amount of the Second Brize be awarded to the Levner Drill as being the best device submitted which embodies what the Committee considers to be the ideal principle in actual drilling, although the drill in its present state is not sufficiently perfected to enable the judges to recommend it for general use. We have the honour to be, Gentlemen, Your obedient servants, Fred. IIellmann (Chairman). J. Harry Johns. Louis G. Irvine. Sam Johns. Walter C. C. Bakes. Joseph A. Mills. W. H. Wood. G. E. Webber. For H. H. Webb. F. H. 11, M. Catlin. Id. Nicholls. Donald Macaulay. Attached to this Report. 1. Dr. Bakes's report on experiments at Simmer East on 8th April, 1903. 2. Memorandum by Drs. Irvine, Macaulay and Bakes on the Chemical and Medical Aspects of Atomisers in Mining Operations. 3. Mr. Wood's Report on Test of Water Feed Air Drills carried out at Crown Reef Mine. 4. Further Report by Mr. Wood. 5. Letter re efficiency of Leyner Drill and replies. 6. Summary and full list of competitors. 7. Minutes of Judges' Meetings. , 8. Statement of Expenditure. PUBLIC HEALTH DEPARTMENT. The Secretary, Chamber of Mines, Johannesburg. Government Laboratory, Pretoria, 23rd April, 1903. REPORT upon Experiments undertaken on the 8th April, 1903, at the Simmer and Jack East Mine, to determine the amount of dust and the humidity under working conditions. The first experiment was made before and during the drilling of a hole whilst Britte. n's Atomiser was workingO1,- and continued after the Atomiser had ceased working. At the very commencement of the experiment the temperature was 74 deg. F., and the relative humidity 88'8 per cent. After the lapse of about 15 minutes the temperature had risen to 77 deg. F., the humidity being the same. Before the drill started working the walls were wetted, and the Atomiser and drill began working at once. After ten minutes the temperature had fallen to 75 deg. F., and the relative humidity had risen to 100. Although the relative humidity remained at 100 per cent., the temperature rose to 76 deg. F. The mine air was aspirated through cotton wool before the drill started working, and it was found to contain 0T875 grams of dust per cubic metre. Whilst the drill and Atomiser were working the air contained 0 2812 grams of dust per cubic metre. Whilst the drill was working after the Atomiser had ceased, the air was found to contain 0-5625 grams of dust per cubic metre. Thus 75 per cent, of the dust produced by the drill was prevented from reaching the aspirator. The second experiment was made before and during the drilling of a hole whilst a spray was being used. The temperature before the experiment was 74 deg. F., but the relative humidity remained at 88'8 per cent, throughout, while the temperature rose to 75 deg. F. during the experiment. The dust before the experiment amounted to 0-3125 grams per cubic metre. Whilst the drill and spray were working, the dust amounted to 0-4000 grams per cubic metre. The increase being thus 0-0875 grams per cubic metre not removed by the spray. As the time did not allow of an experiment being made with the drill and without the spray, it is impossible to calculate the percentage of dust removed. In comparing the two experiments, therefore, we must assume that the two drills produced the same amount of dust. Britten's Atomiser left 0*0937 grams of dust per cubic metre, and the spray left 0-0875 grams per cubic metre. These experiments shew, therefore, that as regards humidity, the spray is preferable because it does not saturate the air with moisture. As regards the prevention of dust they appear to have about the same settling power, the difference in the results being so small. WALTER C. C. FAKES, Govt. Analyst & Bacteriologist to the Transvaal. 8 MEMORANDUM of the CHEMICAL AND MEDICAL ASPECTS of ATOMISERS IN MINING OPERATIONS. 1. The Effect upon the Dust. Anyone who has seen the Atomiser working cannot have failed to notice that there is a considerable decrease in the amount of dust which leaves the face of the rock when compared with that produced when making the dry hole. Actual experiment has shewn that about 75 per cent, of the dust is removed by the Atomiser during the process of drilling. The Atomiser has been shewn to allay a very considerable portion of the dust produced by blasting. Whether the dust produced by blasting is really finer than that produced by drilling is a matter which has not yet been determined. 2. The Effect upon the Gases. The noxious gases met with in the mines are three in number, viz.-- carbon dioxide, carbon monoxide and nitrous fumes. During the process of drilling it may be taken for granted that the only gas which is produced in appreciable quantity is the carbon dioxide, and this results from the breathing of the miners and the burning of the candles. A spray fed with ordinary water will have only a trifling effect upon this gas. The operation of blasting is responsible for the production of carbon dioxide, carbon monoxide and nitrous fumes ; the quantity of the latter gas which is produced varies very considerably with the completeness of the explosion, and this in its turn depends upon the quality of the explosive, the size of the detonator used and so on. Nitrous fumes are produced in greatest quantity when any of the dynamite burns instead of exploding. On some occasions the amount of these noxious gases produced is considerable ; this is evidenced by the appearance of red fumes, and the irritation which is produced after inhaling the gases, of the mucous membranes of the buccal and nasal passages of the miners. When the gases come into contact with the water given off in very fine division from the Atomiser the nitrous fumes are quickly absorbed. Several experiments were undertaken for the Committee, two of which may be detailed. Experiment 1. An aspirator filled with air*containing about 7 percent, of nitrous fumes had a few cubic centimetres of water sprayed into it ; in less than five minutes the whole of the brown colour had disappeared. Experiment 2. About 10 litres of air containing about 10 per cent, of nitrous fumes were allowed to stand over about 10 c.c. of water for three minutes, with occasional shaking. At the end of this time, the nitrous fumes had sunk to 0.5 per cent. After fifteen minutes, the gas was present to so small an extent that no readable absorption could be obtained. 9 The result of these experiments shews that after fifteen minutes the whole of the irritating gases would have disappeared. The Atomiser would have little or no effect upon the CO and C02 . If, however, instead of water, lime water were used, the absorption of the nitrous fumes would be accelerated, and in addition, a small portion of the C02 would be removed from the mine air. It is true, therefore, that the Atomiser would leave the most poisonous gas still present in the air, and this would have to be removed or diluted by fresh air from the compressor. The removal of the irritating gases is, how ever, a considerable gain, quite independently of the removal of the dust. There is a slight disadvantage in removing the nitrous fumes, which are perceivable and irritating, while the more poisonous CO which remains is not so ; this is, that the miner might venture into the drive sooner after blasting than he otherwise would have done. We should therefore allow no relaxation in the regulations concerning the time which must elapse between the blasting and the return of the miner to the face. 3. The Effect of the Atomiser upon the Health of the Miner. The great advantage of the Atomiser is that it allays a considerable proportion of the dust both at the face and in the drives. A possible disadvantage may arise from the supersaturation of the air by the Atomiser. This disadvantage mav be either direct or indirect. a Direct.-- The following facts should be taken into consideration :-- 1. The mine atmosphere is nearly saturated with aqueous vapour. The readings of the wet and dry bulb thermometer show a relative humidity of about 90 per cent. 2. The Atomiser raises the relative humidity of the air at once to plus 100 per cent. 3. The air which the miner exhales is saturated. 4 Therefore the air in the smaller air passages and infundibula, or air spaces of the lungs, must also be saturated. 5. The whole of the excess of moisture would be felt, and probably absorbed by the upper air passages. It seems difficult to conceive therefore, that there should be any important direct deleterious effects from breathing super-saturated air at a temperature of 70 deg. to 75 deg. F. h Indirect.-- The great dangers of working in a nearly saturated atmosphere and proceeding immediately into a colder and drier atmosphere are so well known that it would be useless to dilate upon them. The point for us to attempt to elucidate is the disadvantage of the Atomiser in this respect. Take a Lancashire cotton mill, the relative humidity of the moist room is about 80 to 90 per cent, with a temperature of about 72 deg. F. The relative humidity of the air of the mines is about 90 per cent with a temperature of from 70 to 75 deg. F., without the Atomiser. With the Atomiser the relative humidity rises to 100 per cent., while the temperature sinks a degree or two or remains constant. In the summer the temperature of the Hand varies from, let us say, 60 to 90 deg. F., and the relative humidity from 25 to 80 per cent. In the winter, the temperature varies from 30 to 70 deg. F., and the relative humidity from 15 to 25 per cent. 10 Will the Atomiser make things much worse than they are normally ? --that is, will the extra plus 10 per cent, of relative humidity have any calculable disadvantage ? It is admittedly more enervating to work in a moist atmosphere than in a comparatively dry one. The mine air is under the best of conditions a moist one (about 90 per cent.), and the Atomiser renders the local atmosphere supersaturated. Probably, therefore, working in a supersaturated atmosphere is somewhat more enervating than working in a merely saturated atmosphere. To put it another way, it would be better for a miner to work in the Atomiser air underground, and to return home via a properly constructed change house, than for him to work in the ordinary mine atmosphere and return home direct. Taking all these points into consideration, therefore,-- The mine air is improved by the use of an Atomiser in so far as the dust and nitrous fumes are concerned. The Atomiser has no effect upon the carbon monoxide, and but little upon the carbon dioxide. The presence of an Atomiser does not make the mine air itself appreciably more deleterious ; it makes it more necessary that the miners should use the change rooms which are provided. We consider that it is essential that the water used with the Atomisers should be pure and free from organic contamination, as the use of impure water would constitute a source of danger. 11 REPORT of WATER-FEED AIR DRILLS TEST, , carried out at CROWN REEF G.M. CO., LTD., 1903-1904, for MINERS' PHTHISIS COMMITTEE, CHAMBER OF MINES. This test commenced on Monday, 2nd November, 1903, in which the " Ingersoll-Sargeant " Water-Fed Drill, and the "Water Levner Drill Co's " Model 5 ' Drill " competed. November 4th. . "Ingersoll-Sargeant" Drill stopped 20 minutes for packing. November 12th. "Ingersoll-Sargeant" stopped 45 minutes to put in a new piston, as the chuck was badly eaten away bv water. November 14th. After the shift the new piston put in the " Ingersoll-Sargeant " Drill was taken out owing to the necessity of having the chuck re-bored and a steel bush put in. November 18th. " Ingersoll-Sargeant " delayed 3 hours 45 minutes, awaiting a new drill man and above-mentioned piston. This drill had not been working since the 14th inst. November 19th. "AH work suspended removing drills from 7 th to 9th levels. Both machines stoping up to date. ' November 20th. " Ingersoll-Sargeant " machine sinking a winze, " Leyner " machine driving. November 21st. " Ingersoll-Sargeant " machine prevented from working owing to rock not having been cleared away and a charge having mis-fired the previous evening. November 23rd. " Leyner " stopped 20 minutes to change three pawl springs. November 24th. ; " Leyner " stopped 45 minutes to change two pawl springs. 12 November 25th. " Ingersoll " delayed 30 minutes owing to water connection being choked. November 26th. " Ingersoll " did not work owing to accumulation of water and rock not having been cleared away. November 27th. " Ingersoll " delayed 40 minutes to change front head, which was leaking badly. " Leyner " delayed 35 minutes to change three pawl springs. November 30th. "Ingersoll" delayed for 65 minutes for repacking. December 1st. " Ingersoll " unable to work owing to rock not being cleared in winze. " Climax " water drill was started stoping and put in one drill successfully, but second drill bent and the trial was given up, the drill being taken out of the mine on the 3rd. December 2nd. ' " Leyner " delayed 45 minutes to replace broken water tube. December 4th. " Ingersoll " delayed owing to rock not being cleared in winze. December 7th. " Ingersoll " machine broke piston at the cross holes drilled for her water supply and stopped for the day. December 8th. " Ingersoll " machine re-started. December 10th. " Ingersoll " did not work owing to rock not being cleared. December 11th. Machines changed places--" Ingersoll " to drive and " Leyner " sinking. " Ingersoll " stopped 2-|- hours to change valve on water connection. December 12th. " Leyner " stopped 25 minutes to change one pawl spring. December 14th. ` " Ingersoll " delayed 2 hours for new water valve and air pipe connection. December 17th. " Ingersoll " stopped 15 minutes to clear choked water way. December 18th. " Ingersoll " stopped 1 ^ hours to be generally overhauled. Decmber 21st. Both machines were put on double shifts and run by Italian drill men in place of experts. December 23rd. " Leyner " delayed 45 minutes to change one pawl and two pawl springs. December 24th. " Leyner " delayed 30 minutes changing feed nut. " Ingersoll " machine front head had to be repaired and was not again started until January 6th. December 28th. " Leyner " delayed 45 minutes replacing two springs and one pawl. January 2nd, 1904. " Levner " delayed 95 minutes for new water connection. January 4th. " Levner " delayed 45 minutes for two pawl springs. January 5th. " Levner " delayed 60 minutes to clear water connections. January 6th. Levner " delayed 68 minutes from above cause. Ingersoll started again, but could not work owing to bad leakage, and was delayed 4 hours 25 minutes. January 7th. " Ingersoll " delayed 3 hours 40 minutes with choked water connection, same machine delayed from same cause on night shift 6 hours 45 minutes. " Levner " machine stopped 6 hours 15 minutes to renew hammer head. January 9th. Ingersoll " delayed 1 hour, water connection being out of order, also delayed same day 6g hours from above cause. " Leyner " delayed 6J hours for new pawl springs. January 12th. " Leyner " delayed 6 hours 30 minutes, to replace chuck worn out, also water tube. " Ingersoll " " Levner " Totai, Time Lost eor Repairs. 210 hours 29 minutes. 25 hours 8 minutes. *` Ingersoll " " Levner " Cost of Repairs and Spares. 9 19 71 9-0 6 " Ingersoll " " Levner" Number of* Shifts Worked. 40 Shifts. "Ingersoll" "Leyner" Cost of Repairs per Shift. ... ... ... , ... ... ... , 4/1 If 14 SUMMARY OF WORK performed by EXPERT ROCK DRILL MEN, From NOVEMBER 2nd to DECEMBER 21st, 1903. No. of bits used during test ... . No. of shifts worked ... ... . No. of holes drilled ... ... . Total depth of holes ... ... . Average depth drilled per min. ... . Actual time engaged in drilling ... . Time lost in repairing, underground . ,, ,, on surface . Average air pressure, " Bristol's " recorder u Ingersoll " " Leyner ' 400 951 28 38 194 116 635 ft. 1,011 ft. T81 in. 1-81 in. 69 hrs. 54 min. Ill hrs. 20 min 21 55 6,, 27 ,, 30 ,, 3 55 0,, ,, o,, 61 lbs. 60-8 lbs. SUMMARY OF WORK performed by ITALIAN ROCK DRILL MEN, From DECEMBER 22nd, 1903, to JANUARY 14th, 1904. Xo. of bits used during test ... ... No. of shifts worked ... ... .. No. of holes drilled .... ... .. Total depth of holes .... .. Average depth drilled per min. ... ... Actual time engaged in drilling ... .. Time lost in repairing, underground .. ,, ., on surface ... Average air pressure, " Bristol's " recorder " Ingersoll " " Leyner" 112 541 12 33 25 91 " 111 ft. 411 ft. '68 in. -81 in. 30 hrs. 31 min. 106 hrs. 17 min. 31 ,, 23 ,, 15 ,, 53 ,, 130 ,, 30 ,, 6 ,, 15 ,, 67 lbs. 68 lbs. W. H. WOOD. 15 FURTHER REPORT on ROCK DRILL TRIAL, conducted at THE CROWN REEF PROPERTY, for THE MINERS' PHTHISIS COMPETITION COMMITEE. From the fignres embodied in the detailed report already submitted, it will be seen that the "Leyner" water drill worked much better than the " Ingersoll," and much less delay occurred in the case of the former for repairs, etc. ; also, this machine is much lighter than the " Ingersoll," and, consequently, more easily handled. It will also be noted that the " Leyner " machine ran more regularly and got through more work than the " Ingersoll," both whilst being run bv a drill expert, and also by the Italian rock drill man. The " Leyner," at the termination of the trial on the 14th January last, shewed considerable signs of wear and tear, and it is very probable that if the trial had been continued with this particular machine, the maintenance would have been high. : ' On the other hand, the " Ingersoll " machine, to all intents and purposes, was worn out and could not have run much longer without being practically renewed. Throughout the whole test this latter machine shewed greater constructural defects than the " Leyner," and I am led to think that the former was run as an experiment rather than a fair competitive trial of a proved tvpe of machine. In conclusion, the opinion I have formed after carefully watching the two drills during the trial is that the " Leyner " principle is the better of the two on which to work, but that it contains structural defects which should be over come ; and, further, the machine was not adapted for the air pressure normally used on the Hand. Johannesburg, 6th February, 1904. . :. , W. II. WOOD. 16 Copy of letter sent to Messrs. Hardach, Gazzam, Hay, Pettitt and Hellmann, dated 31st October, 1903 :-- Dear Sir.-- MINERS' PHTHISIS COMPETITION. The Levner Drill has been entered for the above competition, and the Committee are desirous of supplementing the results of their test with reliable information from parties who have had experience of the working of this drill on the Rand. Mv Committee will therefore be greatly obliged if you will favour them with your views and opinion on the Leyner Drill, especially having regard to and dealing in your reply with the following points :-- a. Length of time in use. h. Efficiency of drill as a borer. c. Amount of repairs required as compared with other drills. 1. During the first six months. 2. During the second six months. _ d. Cost of maintenance. <}. Difficulties with steel, if any. f How long the drill retains its first efficiency. g. Whether the drill presents any particular difficulty in handling or is easily workable ; and if the men raise any objection to its introduction. I shall be glad if you can make it convenient to let me have your reply at an earlv date. Yours faithfully. WILL BARNETSON, Secretary to Miners' Phthisis Competition Committee. SIMMER AND JACK PROPRIETARY MINES, LIMITED, Johannesburg, Transvaal. The Secretary, Miners' Phthisis Competition, Box 809. Johannesburg. Mine Office, Germiston, 2nd February. 1904. Dear Sir,-- With reference to yours of the 28th January, I beg to state :-- a. About one vear. b. Equal to Ingersoll-Sargeant in drives, 25 per cent, more efficient in raises. c. Cannot answer this question. d. 11/6 per foot of raise. e. None. f For eight rounds. g. No difficulty, no objection. Yours faithfully, JOSEPH P. GAZZAM, General Manager. 17 KNIGHT'S DEEP, LIMITED. Mine Office, P.O. Box 143, Germiston, Thk Secretary to 4th November, 1903. Miners' Phthisis Competition Committee. 1\<). Box 809. J ohannesburg. Dear Sir,-- In answer .to your favour of the 31st ult. re the Leyner Drill, we only had three of these drills in use for about six weeks, when the hammers, cylinders and valves became so worn that we could only drill about two holes per 9 hours shift with each machine. We are now waiting for these spares to be imported, when we intend to continue their use. a. The drills were in use about six weeks. !>. When perfectly new we have drilled 8 holes oft. Gin. deep with one machine in 9 hours in a rise of about 25 deg. in medium hard blue ground 1,200 feet below surface. e. 1. The amount of repairs required, during first six months would be about double that required for an Ingersoll-Sargeant Drill. 2. Have not had them in use for second six months. d. The cost of maintenance is about double that of other standard machines working in similar ground. e. We had no difficulty with the steel. f We only used the drills about six weeks, when they were in need of the repairs mentioned above : otherwise they were in good condition. g. The drills present no particular difficulties in handling, and are easily workable. The men raised no objection to their introduction. They work much more efficiently with a high air pressure, say 80 to 90 lbs. With the air at 60 lbs. or lower they will hardly work at all. I think the drills very useful for raising only, and that they are the best I have seen for that purpose. They cost more for maintenance and steel than the ordinary machines, but-this, is compensated for by the less cost of getting the dirt out of a rise than a winze, and the extreme difficulty of getting men to work in a rise with an ordinary machine. Yours faithfully, E. E. HARDACH, Resident Manager. WITWATER 8RAND DEEP, LIMITED. Office at the Mine, The Secretary, hojsao Miners' Phthisis Competition Committee, 2nd November, 1903. cvsron Box 809, Johannesburg. Dear Sir,-- THE LEYNER DRILL. In reply to yours of 31st ultimo, I have the following remarks to make : a. Two weeks. b. Bored two holes per shift as compared with five holes by the " Slugger." c. Costly in repairs. cl, c2, d, e and g. Not in use long enough to give a reliable opinion. f. Parts get worn very quickly. Yours faithfully, HENRY HAY, Manager. 18 SIMMER AND JACK EAST, LIMITED, ELANDSFONTEIN. Mine Office, Germistqn, P.O. Box 47, The Secretary, 9th November, 1903. Miners' Phthisis Competition Committee, P.O. Box 809, Johannesburg. Dear Sir,-- In reply to your circular letter of the 31st ult., re Leyner Drill, I beg to inform you that as the drills were only in use here for one month I cannot answer all the questions, but have answered as many as possible. a. One month. ' b. Fairly good as compared with other drills. Cm a'! 1 am unable to answer. d. I am unable to answer. e. The steel used seems to be too light for use in the hard rock here. f. I am unable to answer. g. There is no special difficulty in the handling of this machine, but 99 per cent, of the miners object to using it. Yours faithfully, ARTHUR E. PETTIT, Resident Manager. EAST RANI) PROPRIETARY MINES, LIMITED. P.O. Easf Rand, Transvaal. The Secretary to 7tli December, 1903. i Miners' Phthisis Competition Committee, , ,; Transvaal Chamber of Mines, Johannesburg. Dear Sir,-- In reply to your favour of the 31st October, I now have pleasure in handing you copy of Mr. Penlerick's report on the Leyner Drill. Yours Faithfully, FRED HELLMANN, General Manager. 19 EAST RAND PROPRIETARY MINES, LIMITED. COPY. P.O. East Rand, Transvaal, Fred. Hellmann, Esq., 3rd December, 1903. General Manager, East Rand Proprietary Mines, Ltd. Dear Sir,-- In answer to your letter referred to me regarding the " Leyner Drill." . Time in use, about three months. . 70 per cent, as compared with the Ingersoll-Sargeant. c. 100 per cent, more than the Ingersoll-Sargeant. 1. Not in use for this period. 2. Not iii use for this period. d. 10 per month. e. No trouble with the steel actually, but takes twice as long to sharpen as the ordinary bit. f. Our experience is, that in three months there are a great number of working parts that need renewing, and one great fault is that the cylinder and valve are cast together. g. No trouble is experienced in handling, as the drill is very light, but the men prefer working with an Ingersoll-Sargeant or Holman, and endure the dust rather than worry with the Leyner. Yours faithfully, S. PENLERICK. 20 SUMMARY. No. 1. Respirators and Masks ... ... 2. Dust ExtractorsandHoods ... 3. Water Drills .. ... ... 4. Jets delivering water inside hole ... 5. Jets delivering water at mouth of hole 6. Sprays... ... ... ... 7. Atomisers ... ... ... 8. Medical ... ... ... 9. Miscellaneous ... ... ... ... ... ... ... ... ... ... ... No. of suggestions. 41, ... 35 9 ... 4 ... 60 22 ... 6 ... 15 ... 37 229 No. i; RESPIRATORS AND MASKS. 482 6636 6446 427 833 671 6526 6450 391 396 202 228 209 6706 10 6567 Dr. J. L. A. Aymard Wallach Bros. John Stewart H. J. Lewis Ben Gwilliam G. McCormick Thos. Sheppardson D. Rhys Jones W. H. White Miss H. S. Murphy Thomas S. Morris P. Henshel. W. M. Pascoe C. M. Ulrich Walter SifHeet 6219 E. Nettmann & Co. 44 William H. Wilson 365 E. J. Evans 363 Sidney Fry 231 John C Howe, M.D. 378 H. S. ("over 233 H. A. Stewart 290 Joseph Gervens 486 W. H. Burland, M.D. 369 T. S. Patrick 38 W. T. Jones 479 H. Tiedemann 571 A. Baumach 560] 6707 j Edwin S. Seasells 229 Dr. Jobson Horne 2 11 400 200 545 589 541 575 573 303 6650 Zimmer A Co. John N. Holywell Sir John Macdonald C. E. Heinke Tli. Debaucheron Detrove N. Naill Y. Ducenne Dr. Marcel Monier Dr. Maseaux Adolf Brauer Inhaler. Respirator. Respirator. Respirator. A Silk Handkerchief as respirator. Respirator. Respirator. Mask (using compressed air). . Respirator. Stormont-Murphy Mouth and Nose Shield. Respirator. Face Protector. Respirator. Respirator. Two Indiarubber Teats tilled with cotton wool in the nostrils (acting as respirator). Helmet. Respirator. Respirator. Respirator. Respirator. Respirator. Respirator. Respirator. Respirator. Respirator. Respirator. Large Sponge tied before the nose ; Respirator. Respirator. Plate to he worn in the mouth breathing through nose and eott the nostrils. Respirator. jYl ask. Respirator. Helmet (using compressed air). Respirator (Le Spiro). Respirator. Respirator. Mask. Respirator. 21 No. 2. DUST EXTRACTORS AND HOODS. 513 Henry Niblett 229) 379 [ T. J. Tregonin 1485) "^ 241 George Dickie 12 S. S. Stevenson 495 James Watson 488 F. Anderson 130 James T. Andrew 680 Harley B. Forsyth R. McBrown ) 512 H. G. Farrell [ T. Dickson ) 64 J. C. Elliott . 6411 Stephen B. Williams 227 E. W. Glascock 485 Thomas Powell, M.D. 520a F. M. Jennings 401 J. C. Seaton 6429 Dan Morgan 390 Charles Oldroyd IQ. C. M. Ulrich 38 W. T. Jones 381 Chas. W. Bremis 113 G. Arnall 380 P. McKay 484 A. J. Irvine 289 J. J. Gilbride 6756 W. M. Pascoe 230 Chas. E. Richards 132 F. Andrews 392 John Rees 238 Thos. Clark 25 Chas. Smith 233 A. and Z. Daw 235 E. Raywood 402 V. Trouillet 577 B. Vigouroux 196 August Joppich 195 G. Heiber Dust Arrester. Dust Catcher. . Dust Catcher. Dust Extractor. Dust Extractor. Dust Extractor. Dust Catcher. Dust Extractor. Dust Extractor. Dust Collector (blanket). Dust Extractor. Dust Arrester. Dust Extractor. Dust Extractor and Air Purifier. Dust Collector. Dust Catcher. Dust Collector. Dust Catcher. Dust Catcher. Dust Shield. Patent Dust Catcher (not described) Dust Collector. Dust Catcher. Dust Catcher. Dust Trap. Dust Extractor. Dust Arrester (sponge). Dust Catcher. Dust Catcher. Dust Catcher. . Dust Catcher. Dust Extractor. Dust Receiver. Dust Extractor. No. 3. WATER DRILLS. 6484 C. Beresford Fox 389 ) 474a >J. Whittle & Son, Ltd. 475 j _ 515 lugersoll-Sargeant Drill Co. 403 F. E. Kohlineyer. 93 S. Sykes & Co. 314 Mining Plants Co., Ltd. 528 Courtney W. Thompson 237 William Hopwood 489 Jas. Hosking 6725 Frank B. Bailey Brandt Hydraulic Rotary Drill. New Leyner Rock Drill. Brandt Drill and Leyner Drill. Hosking's Water Drill. 22 No. 4. JETS DELIVERING WATER INSIDE THE HOLE. 403 F. FI Kohlmeyer 389 ). 474a[j. Whittle & Son, Ltd. 475 J 515 Ingerso11 -Sargea111 Drill Co. 93 Sykes & Co. 314 Mining Plants Co. Ltd. 628 Courtney W. Thompson 6525 Thomas Riley 39oj J. W. Holmes 237 William Hopwood 489 Jas. Hosking 648 E. P. .Beaujean Jet of water through drill. Jet of water through drill. Jet of water through drill. Jet of water through drill. Jet of water through drill. Jet of water through pipe in hole alongside the drill. Jet of water through pipe in hole alongside the drill. Jets of water through drill. Jet of water through drill. Jet delivering water inside the hole. No. 5. JETS DELIVERING WATER AT MOUTH OF HOLE. 6381 A. E. Pettit 519 J. Watson 426 P. R. L. Cornes 588) 3841 F. Watt 6644) 306} L. S. Meintjes 6248) 514 F. H. Plummer 389 474a j- J. Whittle & Son, Ltd. 475 482 Dr. J. L. A. Ayrnard 37) 6385 J. H. Battis 6466) 6444 B. M. Tregaskes 64 J. C. Elliott 396 W. FI. White 204 3. B. Hedlev 405 S. T. Gelling ) W. A. McLeod) 393 J. A. Hodge 10 C. M. Ulrich 6511 N. A. Merritt 365 E. J. Evans 517 A. J. Thorne 245 Howard Jones 41 John McTavish 6808 R. J. Renkin 370 Sidney Fry 133 Eugene Kilgore 6813 Hugh M. Lister 40 James Hardwick 243 Chas. L. Smith 42 Thornton Root Jet of water at mouth of hole. Jet of water at mouth of hole. Jet of water at mouth of hole. Sprays at mouth of hole. Spray at mouth of hole. Spray round mouth of hole. Spray at mouth of hole. Spray at mouth of hole. Jet of water at mouth of hole. Jet of water at mouth of hole. Jet of water at mouth of hole. Spray at mouth of hole. Jet of water at mouth of hole. Jet of water at mouth of hole. Steam or water jets at mouth of hole. Jet or spray of water at mouth of hole. Jet of water at mouth of hole. Jet of water at mouth of hole. Jet of water at mouth of hole. Jet of w ater at mouth of hole. Jet of water at mouth of hole. Jet of water at mouth of hole. Jet of water at mouth of hole. Jet of wTater at mouth of hole. Jet of water at mouth of hole. Jet of water at mouth of hole. Jet of water at mouth of hole. Jet of water at mouth of hole. 28 ' No. .5. Jets Delivering Water at Mouth of Hole--Continued. 45 J. H. Baxter 109 Albert H. Wilson 244 Henry Shard 244a W. McTavish 6805 Lewis Horne 882 E. Thomson 862 Donald Ross 371 \V. W. Queen 367 Samuel Hornsby 8981 899 ' James Wallace 788) 888 'J. Beatty 527 Millhouse ik Thomas 487 William Burgess 680 1L B. Squire 649 J. 'Telgate 66 i James Park 741 J. W. Teale 632 Thomas Moore 226 H. Davis. Jun. 252 A. S. Brown 79 II. D. Robinson 807 L. M. McArthur 6504) {)*){)O ) It. J. Pearce 897 (Jeo. J. Tvack oM | 685 - Janies Gitsham 518 J 6807 John Davis 287 William Hop wood 570 M. Gabillnrd 282 Rd. Harle 196 August Joppich 101 lvarle Kolte 6587 Ernst Kramer Spray of water at mouth of hole. Jet of water at mouth of hole. Jet of water at mouth of hole. Spray of water at mouth of hole. Spray of water round mouth of hole. Jet of water at mouth of hole. Jet of water at mouth of hole. Jet of water at mouth of bring. Jet of steam or water at mouth of hole. Spray of water in front of drill hole. Spray of water at mouth of hole. Jet or .spray of water at mouth of hole. Patent dust, layer to deliver jet of water at mouth of hole. Spray of water at mouth of hole. Jet of water at mouth of hole. Jet of water at mouth of hole. . Jet of water at mouth of hole. Jet of water at mouth of hole. Jet of water at mouth of hole. Jet of water at mouth of hole. Jet of water at mouth of hole. Spray of water at mouth of hole. Jet of water at mouth of hole. Jet of water at mouth of hide. Spray of water at mouth of hole. Spray at mouth of hole. Spray at mouth of hole. Jet delivering water at mouth of hole. Spray of water at mouth of hole. Jet or spray of water when drilling. Water from special nozzle when drilling. Spray of water round mouth of hole and a protection plate. 106 B. A. BenhalL 6562 Stephen lingers 40 A S. T. Gelling 4UOj W. A. McLeod 426 P. R. L. Cornes 514 F. H. Plummer 396 W. H. White 6841 6851 Janies Gitsham 518j >6807 John Davies No. 6. SPRAYS. Spray through the compressed air pipe after blasting, &c. Steam Sprays. Spray after blasting. Spray after blasting. Spray after blasting. Spray after blasting. Spray after blasting. Spray upon broken rock. No. 6. Sprays--Continued. 368 W. H. Pengelly 243 Chas. L. Smith 109 A. H. Wilson 244 H. Shard 382 E. Thomson 616 Tom Johnson 371 W. W. Queen 226 H. Davis, Jun. 252 A. S. Brown 661 Jas. Park 482 Dr. J. L. A. Aymard 237 William Hopwood 489 Jas. Hosking 57 6 Touvier. Spray before and after blasting. Spray after blasting. Spray two or three times a day. Spray after blasting. Spray after blasting. Water Sprays. Spray after blasting. Spray after blasting. Spray after blasting, &c. Spray after blasting. Spray or jet of caustic soda and water after explosion blown through compressed air pipes. Sprays after explosion, &c. Spray during and after blasting. 261 Olaf H. Foss. 469 T. J. Britten. 6235 R. H. Jones. 13) 14 ( George Madeira. 587j T. J. Scoble ) John Teague J 582 Georges Hugot. No. 7. ATOMISERS. Spray of air and water round hole. No. 8. MEDICAL SUGGESTIONS. 671 B. Gwilliam 202 Miss H. S. Murphy 485 T. Powell 6449 A. R. Ray 365 E. J. Evans 246 Mrs. Walsh 242) 307) L. M. McArthur 38 W. T. Jones 6405 Dr. F. Bushnell 131 C. Hornbostel 478 Dr. A. E. McCormack 289 Dr. J. J. Gilbride 564 Andre E. Pautere. 581 Dr. Sylvia Labber. 6574 Dr. A. v. Filkorny Cod Liver Oil. Curative Chest Preserver. Diet. Ancient Mariners Oil of Tar. Lung Tonic. A mixture of her own, described in letter. M etapathic Treatment. A patent snuff and mixture. States that the disease is caused bv dust, but specifies no cure. Ozonized Air. Vaseline in nostrils and on lips. Treatment for patients suffering from phthisis. A patent recipe for lung sickness (not described). 25 No. 9. MISCELLANEOUS. 514 F. H. Plummer 426 P. R. L. Cornes 6637 W. M. Drake J216 G. C. Hooper 405 S. T. Gelling W. A. McLeod 361 A. M. Craig 3601 629) R. B. Squire 630j 6806] 288) E. Dunn 10 C. M. Ulrich 378 H. S. Cover 6804 M. Healy 42 Thornton Root 369 T. S. Patrick 6805 Lewis Horne 372 John R. Hill 6812 Mrs. E. Havill 128 A. J. Worrall 380 P. McKay 152 Oscar Katzenberger 230 E. H. Elmendorff 649 J. Telgate 532. J. M. Douglas 526 W. j. E. Sutton. 226 1. Davis, Jun. 373 R. Polkinghorne 366 H. Sargeant 252 A. S. Brown 79 H. D. Robinson -- Dr. N. Sisca 307 L. M. McArthur 91 J. N. Holywell 25 C. Smith 237 William Hopwood 489 Jas. Hosking 648 E. P. Beaugean 101 Karl Kolte 6575 Hermann Rieberer 6586 Chr. Freese Ventilation by Exhausters and Fans. travelling water carriage. Ventilation. Ventilation by Fans. Ventilation. Special Ventilation. Ventilation by Fans and Furnaces. Ventilation, &c. Hygienic Treatment. Ventilating Fans and Drainage. Exhausting Fans. Keeping a pebble in the mouth. Ventilation. Ventilation by Furnaces. Ventilation by Exhaust Fans. Inhalation of Slate Dust. Chest Exercise and Cayenne Pepper. Offers to send something to prevent dust (not described). Patent Drill, &c. Ventilation by Exhaust Fans. Ventilation by Exhaust Fans. Ventilation by Exhaust Fans with connection to hoods over holes being drilled. A Moustache. Ventilation. Ventilation. A method to ensure complete ignition of charge of dynamite, &c. Ventilation, artificial and natural. Ventilation, cleanliness, &c. Ventilation, supervision of men's clothing, housing, diet, &c. Abolition of night shifts and the use of other explosives than gunpowder. Thorough Ventilation. Compounds to neutralise the gases of explosion. Ventilation by Fans. Magnetic Cap. A method of removing gases of explosion. Ventilation, Exhausters to free the air from noxious gases after explosions ; sanitation, etc. Ventilation, Sanitation, Explosives, Change Houses, Baths, etc. Ventilation. Every workman to take sugar during his working hours (sugar best lung medicine). Has a new drill, but does not describe it. Describes some types of drill which give protection to miners.