Commissioner of Agriculture 313 



live stock just landed in a previously uninfected country, or, again, 

 when the disease has been only recently planted but is known to be 

 still confined to a definite and very circumscribed area. The ques- 

 tion becomes important only when the infection has already 

 entered into the channels of trade and has attained a diffusion to 

 an unknown but presumably considerable extent; or, again, if the 

 infection has cropped up at some point in the line of trade, imply- 

 ing indisputably that the disease has had, and doubtless still has, 

 an existence and probably many infected areas further back on 

 that line of traffic, and just as probably many other infected 

 lines have radiated outward from these earlier ones, each leaving 

 at unknown points in its course new centers of infection, and new 

 lines of its dissemination to spread the disease in all directions 

 within large and unknown limits. Under neglect and favoring 

 conditions the multiplicity of infected centers tends to further 

 rapid increase as by a geometrical progression, in which a very 

 short series of advancing steps brings us to an almost inexpressible 

 number of infected points, each as capable of rapid multiplication 

 and diffusion as any one of those that went before it. As already 

 stated, if -the losses over the whole nation should amount to but 

 62 per cent, of that due to a general infection it would still repre- 

 sent $1,000,000,000. 



It must be allowed that, even if left to itself, the losses would 

 not amount to this in any one year, as many extended districts 

 export stock to the large markets but rarely import from these 

 markets, and such districts would long escape infection. Yet, 

 under the conditions supposed, the disease would become perma- 

 nentj and as the stock that have passed through the malady and 

 become immune will to a large extent become again susceptible in 

 the course of 5 months, there is every opportunity for animals 

 within the infected areas tit contract the disease twice in the same 

 vear so that two attacks in the vear and a double loss niav be 

 largely counted on. 



In view of the disposition in the United States, since the out- 

 break in 1902, to exaggerate the mortality and losses from 

 aphthous fever, it seems well to present both sides of the case, that 

 we may be the better prepared to strike a financial balance as 

 between the simple prohibition of all movement and an unbending 

 rule of compulsory slaughter. 



