Appendix 199 



2 : 10 Trotlers in Tail-Male from 



Hambletonian 157 



Mambrino Chief 13 



Miscellaneous (7 horses) 10 



2 : 10 Trotters 180 



At the same period before 1850 there were 

 many thousands of other stallions which were 

 used for breeding purposes and were closely 

 related to these horses. The fact that these 

 other horses have disappeared, as far as the male 

 line of descent is concerned, shows the extent 

 to which breeding operations have eliminated 

 those horses incapable of transmitting energy 

 to their descendants. That the same process of 

 elimination has continued since that time is 

 evident from the fact that the successful lines 

 of descent from these horses is through only a 

 very small proportion of their sons. The process 

 by which this elimination has been brought 

 about in horse breeding can best be described by 

 taking arbitrary numbers for an illustration and 

 then explaining the successive steps in the 

 process. 



Let us assume the early part of the nine- 

 teenth century when there were some hundreds 

 of thousands of horses in the country. These 

 horses will be considered as the first generation 

 and be designated as "Gen. A." The breeders 

 select from these horses 1000 stallions to become 



