1 May, 1899.] QUEENSLAND AGRICULTURAL JOURNAL. 401 
It is a well-established fact that if a tuberculous animal has been injected 
with a large dose or with repeated frequent small doses of tuberculin, it will 
fail to give a reaction temperature on a subsequent testing, unless a considerable 
period (many months) is allowed to elapse for the previous dose of tuberculin 
to be eliminated from the system. 
The following examples serve to illustrate how simple a matter it is for 
animals to be fixed up and sold, in such a manner that the purchaser is perfectly 
satisfied that they are absolutely free from tuberculosis :— 
Case I. 
Mr. A—— has a well-bred Ayrshire bull for sale. 
Mr. B——, an intending purchaser, comes along and says to Mr. A——: 
“T like the appearance of that bull; in fact, I have taken a great fancy to 
him.” 
Mr. A—— says: ‘‘ Well, you can have him for a ten-pound note.”’ 
“ All right,” says Mr. B——, “but now-a-days I get a bit particular; I 
will take the bull on condition that you test him with tuberculin and he shows 
no reaction.” 
This is agreed to by Mr. A——, who invites Mr. B—— to come round in 
two orthree days’ time and witness the test being carried out. 
Now comes the opportunity for Mr. A——, for as soon as his premises are 
vacated by Mr. B—— he injects a large dose of tuberculin into the bull, which 
he has previously proved, to his own satisfaction, has got tuberculosis in an 
incipient stage. The next day, of course, the bull reacts to the tuberculin, but 
the fact is only known to its present owner. ' 
On the following day Mr. B—— comes back with the standard dose of 
tuberculin, which Mr. A—— very courteously allows to be injected into his 
bull; this is followed by a very careful and accurate record of the animal's 
temperature from the twelfth to the twenty-fourth hour after injection, with 
the result that there is no perceptible alteration from the normal before the 
injection. 
Both seller and buyer shake hands and compliment one another on the 
success of thetest, and Mr. B——, after paying his £10, wends his way homeward 
with his purchase, perfectly satisfied that he has a bargain in the animal which, 
in his opinion, is free from tuberculosis. 
Casn IT. ; 
Mr. C is anxious to buy a dairy cow for the purpose of supplying | 
milk to his family. ; 
Mr. D——, a breeder of dairy cattle, is also anxious to meet the require- 
ments of Mr. C 
price. 
Accordingly Mr. C picks out a three-quarter bred Jersey cow, and, as 
it is such a very quiet animal, he is desirous of having it tested with tuberculin 
without further delay. 
The ever-obliging Mr. D—— at once produces the clinical thermometer 
and two small steppered bottles—one bearing the characteristic label of Koch’s 
tuberculin, and the other of Bang’s. 
Mr. C remarks that ‘as there is a great deal in a name, he prefers to: 
use Koch’s tuberculin”; consequently a definite quantity of the contents of 
the bottle labelled “Tubereulinum Kochii” is diluted with weak carbolic 
solution and injected into the selected cow; the records of the animal’s 
temperature taken next day indicate that no reaction has taken place. 
Mr. C then purchases what he conscientiously believes to be an 
animal which has been proyed by the tuberculin test to be free from tubercu- 
losis, and ever afterwards feels proud in informing his numerous friends how 
very much better it is, instead of having a limited quantity of inferior milk 
7 
, and allows him to select any cow in his herd at a certain 
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