Document M4pnBQqrM8Vpd8LrQN8ged9XM

FILE NAME RT Vanderbilt RTV DATE 1955 DOC RTV324 DOCUMENT DESCRIPTION Journal Article - Talc Pneumoconiosis Kleinfeld see JAJ215 BC Notes talc per se does produce a distinct fibrosing pneumoconiosis and it has been suggested that this slowly developing fibrogenic disorder may be allied to asbestosis According to McLaughlin the evidence favors that talc pneumoconiosis is caused only by the fibrous varieties of talc The asbestine variety of the talc found in our study may therefore explain the close resemblance of the ray picture to that of asbestosis It is significant that asbestos bodies first emphasized in talcosis by Gardner are almost invariably present in cases of talcosis in which talc fibers are of an appreciable length p 71 Talc Pneumoconiosis M. Kleinfeld Jacqueline Messite and 1. R. Tabershaw Arch Ind Health ~ 66-72 July 1955 Barry Castleman Comments - talc per se does produce a distinct fibrosing pneumoconiosis and it has been suggested that this slowly developing fibrogenic disorder may be allied to asbestosis According to McLaughlin the evidence favors that talc pneumoconiosis is caused only by the fibrous varieties of talc The asbestine variety of the talc found in our study may therefore explain the close resemblance of the ray picture to that of asbestosis It is significant that asbestos bodies first emphasized in talcosis by Gardner are almost invariably present in cases of talcosis in which talc fibers are of an appreciable length p 71 Talc Pneumoconiosis M. Kleinfeld Jacqueline Messite and 1. R. Tabershaw Arch Ind Health ~ 66-72 July 1955 TALC PNEUMOCON TABLE Compara Talc PneumoconiosPis neumoconiosis MORRIS KLEINFELD M.D. JACQUELINE MESSITE M.D. and IRVING R. TABERSHAW M.D. New York ili! Since Thorel's original study in 1896,1 when talc pneumoconiosis was first recog- nized as a distinct pathologic entity numerous clinical and experimental reports have continued to appear in the literature The bulk of these reports have related to workers in tale mills and mines and to those engaged in the rubber industry Three investigations of the tale industry were carried out in New York State Dreessen's study of 57 men exposed to tremolite revealed an incidence of fibrosis above average 67 but of a nondisabling character In contrast to Dreessen's observations the findings of Porro Patton , and Hobbs based on 15 cases with 5 postmortem examinations showed that pneumoconiosis causing disability and death does occur in talc workers and that patho- logical tissue changes are principally due to talc itself In 1943 Siegal Smith and Green- G burg reported on the dust hazard in tremo- lite talc mining including roentgenologic findings in tale workers and their findings and conclusions were similar to those of the latter Since the roentgenograms and histories of the 32 cases reported on by Siegal and asso- ciates 6 were still available after 14 years a follow study was undertaken in order to 1 ascertain the health status of this group 2 evaluate the present operations and dust concentrations of the talc mines and mills Recorded for publication April 6 1955 From Division of Industrial Hygiene York State Department of Labor * References 2 and 3 References 4 to 6 New 65 and 3 do comparative study of the workers employed before and after the newer engineering techniques had been introduced 1943 The present paper deals largely with the first two objectives the third is now in progress and will be reported at a later date FINDINGS Environmental Data study of the operations and dust concentrations of the tale mills and mines at this time shows a marked improvement in the engineering techniques from that found in 1941 and this is reflected in an appreciable decrease in the dust exposure From 1943 to 1948 a number of corrective measures were insti- tuted to reduce the dust concentrations and included the following a wet drilling in mines b enclosure of elevator and chutes c installation of automatic bagging ma- ) chines d conveyorized car loading e discontinuance of blow rooms and f pro- vision of local exhaust ventilation The dust concentrations obtained at the mills before and after improvements were instituted are summarized in Table 1 Medical Deceased Of the original 32 patients 19 have since died and the causes of death obtained from the hospital records physicians files or death certificates are given in Table 2. No necropsy data are available to confirm the clinical diagnosis The ages of the 19 that died ranged from 48 to 84 years and in the 4 whose cause of death was believed to be due to pulmonary failure associated with talc pneumoconiosis the ages varied between 60 and 79 years Living Thirteen of the original 32 are still alive and of these 7 have retired and 6 are gainfully employed The ages of the re- tired group vary between 63 and 83 years the ages of the actively employed between Brilling wc. eae Mucking General General # Kills Crushing 2.2.2.0... Screening .... Garners and separato Bugging ee . Blow room ....... Open chutes ..... General air ........ * Dust counts are in min } High count due to leaki Patient 1. Age Yr Unknown 63 34 G. Unknown D. II L. F. & 66 Unknown * Causes of death were ( 8 death certificates the clinical and laboral COMM In view of the com ber comprising this in cance can be attached deceased and living gro however that the age workers was between that in the four dece death was believed to insufficiency associateasociate ages varied between though data can be formulated of tremolite talc expos Material may be protected by copyright law Title 17 U.S. Code omparative study of the work- before and after the newer chniques had been introduced present paper deals largely two objectives thethird is ss and will be reported at a FINDINGS of tal Data study the 1 dust concentrations the mines at this time shows a ovement in the engineering n that found in 1941 and this an appreciable decrease in sure From 1943 to 1948 a rrective measures were insti- e the dust concentrations and ollowing a wet drilling in closure of elevator and chutes; on of automatic bagging maonveyorized car loading e of blow rooms and f pro- exhaust ventilation The dust obtained at the mills before rovements were instituted are 1 Table 1 Deceased Of the original 19 have since died and the th obtained from the hospital | cians files or death certificates able 2. No dadta ata are onfirm the cnleincicraol psdyiagnosis the 19 that died ranged from , and in the 4 whose cause of ieved to be due to pulmonary ted with talc pneumoconiosis d between 60 and 79 years irteen of the original 32 - are of these 7 have retired and 6 employed The ages of the re- ary between 63 and 83 years e actively employed between TALC PNEUMOCONIOSIS TABLE Comparative Dust Count Low Data at Several New York State Tale Mines and Mills Original Study 1941 A Medium High Average Follow Study ( 1954 x Low Medkim High Drining 22 eee eee eee eee ee boaaeer Mucking ceceesesereereeeececeeeeee General air cc ceaa eae ee eevee 83 2 + Grinding Garners and separators Bagging 2. cece seen Blok Open room ..... chutes ..., General air oo. es ce swans oe nase 2 9 8 8 8 115 21 60 413 36 18 60 61 70 129 1,190 83 70 2,800 435 6 aD 136 271 728 520 2,180 440 85 818 120 ) 180 69 02 278 151 1,227 125 69 , 3 a 3 8 FA 3 $ 2 -fl 4 12 : an 13 360 35 68 15 40 9 21 16 90 Discontinued Discontinued 19 a0 3 4 oe 53 25 338 11 23 19 * Dust counts are a million particles per cubic foot + High count due to leakage from conveyor enclosure TABLE Causes of Death in Talc Pneumoconiosis D. F. A. G. Q. K. L. F. Age Yr Cause of Death * Unknown Fractured skull 63 Carcinoma of G.I. tract 84 1 Hypertensive cardiovascular 2 Cerbral Cerebral hemorrhage Cerebral 53 1 2 General hemorrhage arteriosclerosis 60 1 Pulmonary insufliciency - -paeumoconiosis 2 Congestive heart failure Unknown 9 Unknown 68 Acute myocardial infarction 68 56 Unknown Acute myocardial infaretion Acute myocardial infarction Mesothelioma of pleura moeonosis bilateral Patient L. C. L. M. Age Tr 62 57 65 W. M. 68 W. 48 * Cause of Death Acute myocardial infarction Carcinoma of stomach Carcinoma of pancreas ro Pulmonary failure associated with preumoconiosis Duodenal ulcer L. 9 72 J. R. 79 C. T. B. Laknown 58 Pulmonary failure due to preumoconiosispreumoconiosis 1 Paeontosls 2 Myocarditis : Unknown Carcinoma of G.1 tract * Causes of death 3 death certificates were obtained from the following sources 1 private physicians 2 hospital records and 45and 64 years A summary and analysis of the clinical and laboratory findings are seen in Table 3 COMMENT COMMENT In view of the comparatively small num- her comprising this investigation no signifi- cance can be attached toage incidence of the deceased and living groups Itis noteworthy however that the age range in the retired workers was between 63 and 83 years and that in the four deceased whose cause of death was believed to be due to pulmonary insufficiency associated with talcosis the / ages varied between 60 and 79 years Al- though no statistically significant correlative datacan be formulated between the duration of tremolite talc exposure and longevity it is of interest that an above average life span may occur following prolonged exposure to tale dust and associated with pulmonary dys- function Tables2 and 3 Analysis of the medical data of the living shows many similarities to those reportedin the literature Clinically the outstanding features are dyspnea productive cough ab- normal chest findings diminished breath sounds basal rales limited chest expansion clubbing and a roentgenographic picture picture de- scriptive of pneumoconiosis Clinically the courseis relatively slow but progressiveand similar to silicosis the clinical picture does not retrogress with marked improvement of the industrial environment or upon retire- ment Dyspnea is present in 100 of the group and is sufficiently pronounced to limit t References 5 to 7 Material may be protected by copyright law Title 17 U.S. Code % TABLE 3. Symptomatology of Talc Pneumoconiosis Clinical Picture Patient F. Age * Yr Status 62 R Environmental Exposure Fr. Tale mil : Syruptoms + ace + Dysp- Cough nea Mi S P oe Signs + Tungs distant basal Emphysematous Heart Kn Nn Olubbing Roentgenologic Findings Roentgenologic 4 tem tae oe Progres sion t Compli- cations Plaques + S S Bullae Cor pulmonale EKG EKG Rt.V.H. pattern Peripheral blood WBC High RBO WBC 15.5 5.15 9.1 84 M. G. W Tale roill None Mi Br sounds distunt Aluminum Emphysematous Not None enl Mi Hilar nodes Fr. cnl Normal 15 5.16 11,1 Materil W. 49 W Tak mill Steel mill S Mo S Clear to palpation Not Mi P und auscultation em J. J. 49 W Tale mil 301 S S distant sounds Col. Mo Hilar nodes Pr $ Cor pulmonale Pr ceneaeeae B1.V.II. 16.5 8.6 16.5 5.21 13.8 throughout P Rmphysematous Rmphysematous may W 1 R. Tale mill MI Mi Rules and wheezes Not Mo Mi None P throughout enl be C. 88 R Tale 40 | 8 g Br sounds distant Not Mi Mo None pattern Not pr fee eeee 15 5.01 11.8 Pr Abnormal 15.5 5.00 9.8 P Rales throughout enl rhythm Emphysematous V. L. 45 W Tale mine 20 Mo $ Br sounds distant Not None S Bullue Pr Rales bazal enl Hilar nodes Emphysematoust en protecd Pr S. P. 68 20 Pale ping 5 50 Mo Tale milk P by Tales Zine nine Br sounds distant Not Mi basal gol Emphysematous Mo None Normal 10 5.12 7.1 Lt.V.H. 16.5 5.2 7.8 pattern K C. 73 Tale mill Mi Mo Br sounds distant Not None Mo Nune Other quarries I Kales busal enl Pr Normal 16 5.18 9.1 copyright -17 W. 69 R Tar and mines Euphysematous En Pr Mi 8 Br sounds distant P Rales throughout Mo S Hilar nodes eul Emphysealous Emphysealous LLY.II. 14.2 1.61 8.8 pattern law Nonspecifie W. 63 W Tule raill 30 Mo sounds distant Not Mi Rales througbout enl Emphysematous Mu Bullae Pr 14.4 4.71 13.1 wave changes 79 R R. Tale mill - 24 Mo Mo Emphysematous Rules basal Title P R. 70 R Tale mill None Mi Kales basal Not Mi enl Not Mi Mo Hilar nodes Pr enl Mi Tilar nodes Pr tipeaeene 12.2 3.5 10.2 Baso- 17 enl eol philos % U.S. * Status Retired W Working + Minimal Mo Moderale Severe Productive Present } Exposure to tale only Code the tersital the the worker Of ordinary worker ordinary tersti al ordinary to ordinary ordinary infltraion ordinary ordinary extrm moderate routine routine infltraion routine infltraion routine of physic 10.2 13.1 4.71 bane 14.4 putern Nonspecifwave rey Fr. Pr. Pr, nodes nodes en), Bulae Alarend, Hilar unl, OW of Mi Mi Bi} Mi + Not en). fe) <6 Z 5 4 basal Emphyseatou Emphyseatoubasal basal basal throughout basal Emphysematous Presnt Rales Rales Rales Kales Rales Rales Pr 00 Mo Mi Mi Productive None Productive / Mo None None None $ : : t 24 24 mil mil Sevre Inines31 Inines31 mill Working ModeratWorking Tale Tale Tale M "fi only Retird tale 80 to Staus-Minmal Exposure Mi * PNEUMOCONIOSIS Fig 1A Patient S. W. 1941 characteristic basal infiltrations are seen B Patient S. W. 1954 note giant bulla in N. U. and prominent hilar markings the ordinary routine physical activity of the worker to a moderate degree Of extreme interest are the findings in terstitial infiltration of variable intensity located basally and in the midlung fields and of bilateral distribution with the apices relatively spared In several the infiltration is nodular in character Emphysematous bullae of varying sizes are observed in four Fig Fig 24 Patient B. B. 1954 pericardial pericardial 1941 pericardial and diaphragmatic plaques are seen B. Patient B. M. 1954 pericardial and diaphragmatic plaques are more pronounced Material may be protected by copyright law Title 17 U.S. Code A. M. A. ARCHIVES OF INDUSTRIAL HEALTH 14 and B A most striking finding is the presence of opaque densities varying from singlesingle linear strands in the region of the diaphragm to massive deposits bizarre in shape extending extending over a large part of the lang field and occasionally ) cardium Fig2A and by. referred to as talc plaques on the periThese deposits Siegal Siegal and as- sociates are observed in all but one of the enlargement enlargemnt pres- cases studied Cardiac ent in four persons in two enlargement is of whom the configuration is suggestive of cor 1941. As mentioned previously two of the present chest x - showed cardiac rays con- figurations suggestive of cor pulmonale but significance of even added a markedly de- creased cardiac silhouette is noted in one pa- tient G. S. and is strongly suggestive in another The cause for this is not clear It is possible that pleural pericardial adhesions associated with the plaque formation and subsequent retraction and limitation of pericardium may possibly account for this decreased cardiac silhouette Fig 3. A Patient J. J. 1941 marked basal infitrations are noted B. Patient J. J. clinical 1954 progressivpe rogressive infiltration extending to upper lobes is seen there is a dilated heart clinical picture is one of cor pulmonale pulmonale The pulmonary arteries and branches are prominent ina number of the chest rays When comparisons are made with with the roentgenograms taken in 1941 it is of interest to note that although variable progression occurred in the majority of the patients Fig 34 and B the most out- standing revelation is that what in retrospect had appeared to be severe pulmonary involve- original ment in the original sidered in the series cannot be so con- light of a year interval Furthermore the hilar hilar adenopathy which is scen in six of the present series in retrospect was also present in three of the rays in 70 70 No correlation between symptomatology and ray findings is noted and this has appears been observed by Although the series is small thereappears , nevertheless nevertheless trend between the degree of clubbing and chest ray involvement those with severer clubbing show more extensive pulmonary in- volvement Six out of 11 show abnormal electrocardio- graphic configurations such as a pattern of right ventricular hypertrophy 2 ( pattern of left ventricular hypertrophy 2 References 6 and 8 TALC PNEUMOCONIO c abnormal rhythm specific wave alteration suggestive trend betweel normal normal electrocardiogra five five whose electrocardio only one shows clubbing mal degree ; in the six wil cardiograms clubbing va ate to a marked degree two with the right trophy pattern It is not of cor pulmonale The in in in tremolite pneumocon however histologic evide eral investigators conf relationship Jaques and reported not only only genera the alltthhee pulmonary arterie largement associated wit monary talcosis but als involvement of myocardi the paucity of the av data on human pulmonary anism underlying the pulmonaleis not clearly The peripheral blood markable and indicate t blood does not reflect th changesassociated with t The workers presently developed developed and well nouris observations made by ciates and no reason ca plain this apparent differi The results of the pre the findings of other inv per se does produce pneumoconiosis and it E that this slowly develop order may be allied to as ing to McLaughlin the tale pneumoconiosis is fibrous varieties of talc T of the talc found in our st explain the close resembl picture to that of asbestos that asbestos bodies fit talcosis by Gardner arc present in cases of talcos Material may be protected by copyright law Title 17 U.S. Code OF INDUSTRIAL HEALTH tioned previously two of the rays showed cardiac con- gestive of cor pulmonale but significance a markedly de- silhouettesilhouette is and is strongly noted in one pa- suggestive in pericardial cause forthis is not clear It pleural pericardial adhesions 4 the plaque formation and raction and limitation of the ay possibly account for this iac silhouette notedB PatienJt. J. 1954 > is a dilated heart clinical dion between symptomatology dings is noted and this has 1 by others Although the , there appears nevertheless a 1 the degree of clubbing and volvement those with severer more extensive pulmonary in- | 1 show abnormal electrocardio- pattern urations such as a ricular hypertrophy 2 b hypertrophy ventricularhypertrophy 2; TALC PNEUMOCONIOSIS c abnormal rhythm 1 and d non- specific wave alterations 1 There is a suggestive normal trend between clubbing and abelectrocardiographic findings In five whose electrocardiograms are normal only one shows clubbing and this to a mini- mal degreein the six with abnormal electro- cardiograms cardiograms clubbing varies from a moder- ate to a marked degree being severest in the two with the right ventricular hyper- trophy pattern It is noteworthy that in the latter two the clinical picture is characteristic of cor pulmonale The incidence of the latter in tremolite pneumoconiosis is unknown ; however histologic evidence reported by sev- eral investigators confirms an etiological relationship Jaques and Benirschke have reported not only generalized thickening of all the pulmonary arteries with cardiac en- largement associated with progressive pul- monary talcosis but also a granulomatous involvement of myocardium per se In view of the paucity of the available pathological data on human pulmonary talcosis the mech- underlying the development of cor pulmonale is not clearly defined The The peripheral blood findings are not re- markable and indicate that the peripheral changesblooddoes not reflect the physiopathologicphysiopathologic changes associated with talc pneumoconiosis The workers presently observed are well developed and well nourished in contrast to the observations made by Siegal and asso- _ ciates and no reason can be offered to ex- plain this apparent difference The results of the present study confirm the findings of other investigators that tale per se does produce a distinct fibrosing pneumoconiosis and it has been suggested that this slowly developing fibrogenic dis- order may be allied to asbestosis Accord- ing to McLaughlin McLaughlin the evidence favors that take pneumoconiosis is caused only by the fibrous varieties of talc The asbestine variety of the tale found in our study may therefore explain the close resemblance of the ray picture to that of asbestosis It is significant that asbestos bodies first emphasized in talcosis by Gardner are almost invariably present in cases of talcosis in which talc fi- bers are of an appreciable length This has been observed histologically by several in- vestigators fi and by ourselves || In essence this pneumoconiosis consists of a dense fibrosis which is particularlyprevalent peri- bronchially and perivascularly and occurs in sheets occasionally assuming assuming a nodular con- figuration the latter finding has been sug- gested as representing a reaction to the quartz content of the talc The hilar lymph nodes are generally described as showing no en- largement or fibrosis and on microscopic ex- they amination are reported to contain talc- laden macrophages and the tale content to be of considerable magnitude It appreciated that some of the workers may have been exposed to a relatively high concentration of quartz at some phase of their operation but it appears highly unlikely that this was uniformly present for all the workers particularly in view of the con- sistent finding of low free silica content in both the mills and the mines Furthermore evidence has been presented by recent in- vestigators{{ that moderately advanced pneu- moconiosis is caused by tale in the absence of any silica in the tale mixture or in the atmosphere It is not unlikely that some of the commercial preparations of tale which have different mineralogic and chemical characteristics as pointed out by Hogue and Mallette may require a long exposure be- fore chest ray evidence or symptoms ap- pear From observations of Siegal and as- sociates 10 years are required between ex- posure and onset of symptoms factors What the specific are in the causa- tion of talc pneumoconiosis are not known There is need for more epidemiologic studies where environmental conditions are well con- trolled and the life course of the worker is closely followed This would permit a better statisticalstatistical analysis of data than is now possi- mentalThereis alsoa need for further experimental and biochemical researchin this field andit is more than likely that the utilization of all three approaches will lead to the estab- | Kieinfeld M Unpublished data from personal observation f References 9 and 10 71 Material may be protected by copyright law Title 17 U.S. Code ARCHIVES OF INDUSTRIAL HEALTH lishment of better definedcriteria and a clearer understanding of the mechanism and pathegenesis of talc pneumoconiosis SUMMARY AND CONCLUSIONS The health status of a group of 32 tale workers tories whose roentgenograms and hiswere available after 14 years were restudied and the following data were ob- tained 1. Nineteen of this group had died their ages at death varied between 48 and 84 years In four whose death was believed due to pul- monary failure associated with tale pneumoconiosis the ages varied between 60 and 79 years Of the living six are gainfully employed 2. The outstanding clinical features involve the pulmonary and cardiovascular systems Dyspnea and cough are frequent Emphysema basal rales diminished diminished chest expansion and clubbing are the striking physical findings 3. The characteristic chest ray is that of a diffuse infiltration of the basal and midlung fields with occasional nodularities seen Emphysematous bullae hilar adenopathy and cor pulmonale are not infrequent Tale plaques located in the region of the diaphragm pericardium and extending over a large part of the lung field are consistently observed but do not reflect the degree of pulmonary involvement Likewise no correlation between symptomatology and ray findings is observed electrocardiograms 4. Abnormal are seen in six and include patterns of right ventricu- lar hypertrophy two and left ventricular hypertrophy two abnormal rhythm one and nonspecific wave alterations one The two persons demonstrating a right ventricular hypertrophy had pattern between other other features suggestive of cor pulmonale There is a suggestive trend degree other clubbing and abnormal electrocardio- graphic findings graphic graphigracphic graphic remarkableperipheral 5. The blood findings are not and do not reflect the changesin the pathophysiology of this disorder 72 6. In general the workers appear well developed and well nourished in contrast to observations reported in 1941 progression Although was observed in all the clinical course is relatively slow and in spite of the presence of moderate infiltration and pulmonary dysfunction six of the work- ers are still actively employed The marked improvement in engineering methods is reflected in an appreciable de- crease in the dust exposure The pathologi- cal picture however did not retrogress with improvement of the industrial environment or upon retirement Assistance was rendered in the present study by Dr. Jesse R. Patton of Ogdensburg N. Y. by Mr. John Kean Superintendent and Miss J. Bishop of the Ray Department of Edward Noble Hospital Gouverneur N. Y. and by our Industrial Hygiene Engineering Unit REFERENCES ; 1. Thorel .: Die Specksteinlunge Beitr path Anat 20:85 1896 Marshall 2. G. and Perry K. M Dis Chest London262 1952 3. McLaughlin A. .: Cited by Doig A. .: Other Lung Diseases Due to Dust Postgrad Med J. 639-649 Dec. 1949 4. Dreessen W. .: Effects of Certain Silicate Dusts on the Lungs J. Indust Hyg 66-78 March 1933 : 5. Porro F. W Patton J. R. and Hobbs A. Pacumoconiosis in the Tale Industry Am J. Roentgenol 507-524 April 1942 6. Siegal W Smith A. N. and Greenburg L Dust Hazardin Tremolite Talc Mining Including in Roentgenological Findings Talc Workers Am j Roentgenol 11-29 Jan. 1943 7. Mann B. and Deasy J. .: Tale Pacumo- coniosis in the Textile Industry Brit M. J. 1460- 1461 Dec. 18 1954 Dalla 8. Dreessen W. C. and Valle J. M Effects of Exposure to Dust inTwo Georgia Talc Mills and Mines Pub Health Rep 131-143 Feb. 1935 9. Jaques W. E. monary Talcosis with and Benirschke K PulInvolvement of the Stomach and the Heart A. M. A. Arch Indust Hyg 451-463 May 1952 10. McLaughlin A. I. G Rogers E. and Dun- ham K. C. Tale Pricumoconiosis Brit J. Indust Med 184-194 July 1949 11. Hogue W. L. Jr. and Mallette F. .: A Study of Workers Exposed to Talc and Other Dusting Compounds in the Rubber Industry J. Indust Hyg & Toxicol 359-364 Nov. 1949 PneumoconPio neumoconio South India GEOFFREY E. FFRENCH M. Oakville Ont Canada INTRODUCT Pneumoconiosis has be condition in the Kolar 1940 ccontionuesntinues to be because because countered It does not j itself as a clinical disease of the word but rather as dition The potential dange with tuberculosis which working of quartz , varying from a few varying width width width whicwhich h dip at at a sh . considerable of lengthof tim depths depths down to 9900 ft and are being worked dry-dry- and bulb tempera use the of water dust cluded + The quartz reef 3 ing widthswidths of lode matrei pore Recorded for publication _ Formerly Kolar Gold Senior The Kola horder of Mysore and 78 18E. Material may be protected by copyright law Title 17 U.S. Code