Xo. 4.] CATTLE COMMISSIONERS' REPORT. 535 



licenses provided by law, where this business is being con- 

 ducted and the product disposed of in the market without 

 being inspected. This evil is one that will become less and 

 finally be corrected under the operation of the present law. 



It is further possible that a certain small proportion of tuber- 

 culous meat may find its way into the market by reason of the 

 animals not being inspected at the time of slaughter, because 

 the owner had received a certificate of soundness of such 

 animal, based upon physical examination, within six months 

 prior to the slaughter ; and, finally, in addition to this, there is 

 undoubtedly a small amount of tuberculous meat now finding 

 its way into our markets that comes from animals which have 

 been killed just without our borders in the neighboring States. 



The milk now being sold in Massachusetts is derived from 

 home herds and from herds which are maintained outside the 

 limits of the State, the product of which is regularly marketed 

 in Massachusetts. Inasmuch as it is impracticable to see that 

 the milk supply itself is pure except by purifying the animals 

 from which it is derived, it follows that there is no practicable 

 means whereby this State can assure the consumers that milk 

 coming from without its limits is free from the contagious 

 principle by any prescribed system of examination relating to 

 the cows from which it is derived, because the Commonwealth 

 has no jurisdiction over those animals. The only practicable 

 method of overcoming this difficulty is to provide, in some 

 form, that milk shall not be delivered in this State except 

 that coming from animals which have been properly shown to 

 be free from disease. 



On Nov. 20, 1894, the Board, in its circular letter of that 

 date, which will be found printed on page 186 of the report of 

 that year, made the following declarations : — 



First. — That tuberculin is a reliable agent for determiuiug the 

 presence of tuberculosis in cattle. 



Second. — That tuberculin, properly prepared and carefully han- 

 dled, can have no injurious effect upon healthy animals. 



Third. — That it is the only known means whereby a positive diag- 

 nosis can be made in the earlier stages of the disease. 



This declaration was based upon the experience which mem- 

 bers of the commission had had up to that time, covering 



