Experiments and their Verification 195 



The hind feet in previous trial showed a lack of distance between 

 them, and by paring inside of both we gained an increase from 4.3 in. 

 of previous trial to 7 in. in this trial. Her gait was therefore more 

 open, as intended. 



There being also an uphill trial, I give the extensions of both in 

 Fig. 151. Although the stride of the downhill was naturally longer 

 (15.02 ft.) than that of the uphill trial (14.36 ft.) by 8 in., there was 

 a slight increase in the separation of the extremities (about y in.) 

 and the overstep of hind over fore on either side was a good deal less, 

 namely, 0.4 ft. or 4.8 inches, though this difference is not excessive, con- 

 sidering the shorter stride. It stands to reason that there was in the 

 uphill trial a good deal more exertion at propulsion, as the variations 

 from each average stride will prove, namely: 



DOWNHILL. 

 Total Var. Total Var. 



. Fore Hind 



Near. Off. Near. Off. 



+ 1-73 J -7 8 .+ 1-72 1-27 + 1.49 1.84 + 2.04 2.39 



3-51 2.99 3.33 443 



UPHILL. 



+ 2.40 2.58 +2.95 2.80 +3.19 3.09 +3.29 2.99 



4.98 5.75 6.28 6.28 



The hind feet seem to have less forward extension, as the dif- 

 ference in the oversteps will show. The reason that the separation 

 of extremeties is not greater (3.18 ft. 3.12 ft. = 0.06 ft., or y^ in.) 

 lies in the fact that the fore feet also tend to have more backward ex- 

 tension going uphill. The off fore that was behind the near fore going 

 downhill points back still more, and the near hind that pointed for- 

 ward going downhill now ceases to do so going uphill. With this 

 greater action of hind we lose therefore the too free activity of the 

 near hind, and the result is that the extension of both hind becomes 

 more equal than it was going downhill. 



This incline of the track was surveyed and showed on the stretch 

 used for the experiments the following grade : 



14 inches in 400 feet. 



