NIPHER EVOLUTION OF THE AM. TROTTING-HORSE. 5O9 



The Evolution of the American Trotting -Horse.* 



By Francis E. Nipher. 



In the American Journal of Science for April, 1883, Prof. W. 

 H. Brewer has furnished data for the discussion of the change in 

 speed of the American trotting-horse. His table is here repro- 

 duced. 



TABLE SHOWING THE NUMBER OF HORSES UNDER THE RESPECTIVE 

 RECORDS. 



Prof. Brewer states that the data for the speeds 2 130 and 2 :27 

 are very unsatisfactory, but for all the others are reasonably 

 correct. 



On taking the logarithms of all the numbers A^ of horses capa- 

 ble of trotting'a mile in s seconds, it results that the plotted val- 

 ues of log. N for their proper dates give a straight line for each 

 value of s. For the speeds ^ of 2 130 and 2 :27 these lines are 

 parallel . to each other, and the lines representing the remaining 



Read May Vth, 18S3. 



