Contagious or Epizootic Abortion in Cows. 
89 
venture to think there is not the slightest doubt that it would 
well pay a tenant to mole drain heavy land, even if the 
landlord did not bear any of the cost, but the question of 
future compensation would probably lead to trouble, especially 
if the land after draining should prove to be worth a greatly 
increased rent. 
I hope these notes may draw the attention of land owners 
and farmers to this simple and cheap method of considerably 
improving wet, heavy land whether arable or pasture, for it is 
well worthy of their consideration. I am indebted to Messrs. 
John Fowler & Co. of Leeds, the makers, for the illustrations 
of mole ploughs, and to Messrs. Briggs & Sons, of Stamford, 
who have carried out a great deal of mole draining for me, for 
various particulars. 
Douglas T. Thking, F.S.I. 
1 Sheep Street, 
Northampton. 
CONTAGIOUS OR EPIZOOTIC ABORTION 
IN COWS. 
The purpose of this article is to describe in language that may 
easily be understood by a layman the present state of know- 
ledge with regard to abortion in the bovine species. It hardly 
requires to be stated that the failure of cows to carry their 
calves to full term may be the result of various untoward 
circumstances, including all those that seriously injure or 
threaten the life of the pregnant animal herself. Thus, abortion 
may be caused by mechanical injury, severe diseases of various 
kinds, poisoning, starvation, and possibly severe mental shock 
or fright. Although it is admitted that these must be reckoned 
as possible, and occasional actual, causes of abortion, they 
are, even collectively, of little or no practical importance, 
from the simple fact that in the immense majority of cases 
of abortion in cows there is strong evidence that none of 
them has been in operation. What these suggested causes 
particularly fail to explain is the occurrence of multiple cases 
of abortion in the same herd in one or several successive 
seasons. Very slight reflection regarding the various diseases 
of man and animals which have this character of affecting 
considerable numbers of individuals living in more or less 
close association, will show that the great majority of them 
are contagious or infectious, by which is meant that the cause 
of the illness is a living organism which multiplies in the 
