1911] on Travelling at High Speeds on Surface of Earth. 121 



an hour for 100 yards, falls to 74 miles an hour as the average speed 

 for a distance of 100 miles. 



"We do not know the speed of the original historical run from 

 Marathon to Athens, but we do know that Dorando ran the modern 

 Maratlion from "Windsor Castle to the Stadium at Shepherd's Bush, 

 a distance of 26 miles 885 yards in (to be exact) 2h. 55m. isfs., 

 or at the rate of 1) miles per hour, which, you see, fits very well on 

 our curve. 



"We may notice in passing that in walking fast and starting to 

 run the arms swing in time with the opposite leg, as in the modern 

 picture on the diagram exhibited. In the picture, however, copied 

 on the same diagram from an ancient Greek vase, although the atti- 

 tude of the legs is the same, it might appear at first sight as if the 

 arms were swinging in the contrary way. As a matter of fact, a 

 closer examination shows that in all the figures on the vase the arms 

 are in the same position, although the legs are in different phases. 

 This seems to indicate that the arms of a Greek runner were held in 

 a fixed position as shown, and, from the position of the hands, with 

 the evident intention of cutting the wind. If this is true, it indicates 

 that even then it was clearly recognised that if there was any effect 

 of the wind it was just as important behind as in front, a matter I 

 shall have to allude to hereafter. 



What man can do by his muscular effort in the water is shown by 

 the small curve in the corner. The greatest distatice shown (Fig. 2) 

 is about 21 miles by Captain "Webb at about 1 mile per hour, al- 

 though for a short distance it will be seen that a man can swim at 

 about 4 miles per hour. I do not put in flying, because man has 

 not yet flown by his own muscular effort, and flying men to-day are 

 using engines of from 20 horse-power to 100 horse-power, i.e. "from 

 200 to 1000 man-power. Gliding per se is no more than falling 

 through the air (more or less) gradually, as in a parachute. 



Before proceeding to see what man has done to increase his 

 powers of purely muscular locomotion by means of mechanical 

 devices we will study the details of locomotion in the other animals. 

 We are able to do this by the method of Mr. Muybridge, since 

 developed in the invention of the kinematograph, and which was 

 explained by Mr. Muybridge for the first time in this country about 

 thirty years ago in a lecture in this hall. 



Take, first, the galloping horse. The lantern diagram shows 

 clearly the various phases in the action of a horse, and shows how 

 the animal is not only able to attain its high speed by its length of 

 stride, but by doing what man cannot do to the same extent — draw- 

 ing up its body and in springing forward, using alternately its fore 

 and hind feet, so as to get a stride which no two-footed creature 

 could attain on the level ground. I may point out that the kangaroo, 

 though using only two legs, makes effective use of its tail in the 

 spring. The horse springs clear of the ground off its forefeet, only 



