CHAPTER VII. 

 TUBERCULOSIS. 



The relation of micro-organisms to infectious diseases is ad- 

 mitted to be very intimate ; and although it may not be quite so 

 universal as some are inclined to assume, it is nevertheless definitely 

 proved to exist as regards some of the infectious maladies affecting 

 man and brutes. 



In all investigations of the relative micro-organisms to disease it is 

 necessary to bear in mind, as Koch pointed out, that no observation 

 can be said to be complete, or one should rather say in no instance 

 ought to be accepted, unless it has been satisfactorily proved after the 

 strictest microscopic examination during a long series of experiments. 



To show how careful students should be before accepting opinions 

 which are fluently expressed by even experienced cattle men on the 

 subject of tuberuclosis, no less an authority than Dr. E. Klein says : 

 " According to my own experience, extending over a very large num- 

 ber of cases of human miliary tuberculosis and tuberculosis of cattle 

 1 cannot for a moment accept the statement that the bacilli found in 

 the two affections are identical, ior I find that in the two liseases 

 their morphological characters are conspicuously larger than those 

 Of the tuberculosis of cattle, and in many instances more regular y 

 granular." 



When Dr. Klein made this statement he held the important position 

 oi Lecturer on General Anatomy and Physiology in the Medical 

 School of St. Bartholomew's Hospital, London. But it is not my 

 purpose to discuss points in connection with tuberculosis outside the 

 dairymen's sphere of observation which embraces causes and effect 

 from that standpoint. So -far as our history goes, tuberculosis was 

 practically unknown among the dairy herds of the Camden and West 

 Camden districts forty years ago. It almost goes without saying that 

 it was introduced into those districts through the introduction of the 

 fashionable breeds of beef cattle in the seventies and eighties ; and 

 was subsequently disseminated by persons obiaining virus for inocula- 

 tion purposes during occasional outbreaks of contagious pleuro- 

 pneumonia. That there may have been isolated cases in the lliawarra 

 and Shoalhaven Valley districts prior to 1870 no one will dispute; 

 but, if so, no one seems to have noticed it, and most dairymen prior 

 to that date, and for many years afterwards, slaughtered their own 

 beef, and as a rule the boys on the farm are very observant when 

 slaughtering cattle for their own consumption. 



From 1850 to 1870 Sydney doctors constantly recommended their 

 consumptive patients to visit the South Coast in search of cows' milk 

 and health. Drs. Tarrant, Terry, and Beath, whose professional ex- 

 perience, taken in the aggregate, extends over thirty years (and living 

 as they did in the midst oi the dairying centres, their combined ex- 

 perience is worth much), say : " Human tuberculosis is very rare 

 indeed on the South Coast." This bears out the opinion once ex- 

 pressed by a well-known Sydney medical man to the writer, viz.: 

 " Many thousands of children die annually from the want of mi k as 

 it is taken from the cows, but very few indeed die from the effects 

 of such milk." 



Everyone knows, without being told by a scientist that if the 

 system is in a position to assimilate plenty of ricTi milk there is very 

 little danger of being attacked by tuberculosis, provided the milk is 

 forthcoming. In the "Elements of Medicine," Dr. Carter says: "In 

 order that the growth and development of the tubercular virus may 



263. 



