864 KEPORT— 1893. 



So also the power of the living human mechanism to withstand widely diverse 

 and excessive strains is altogether unapproachable in artificial constructions. Thus, 

 although fitted for an external atmospheric pressure of about 15 lb. per square inch, 

 he has been able, as exemplified by Messrs. Glaisher and Coxwell in 1862, to ascend 

 to a height of 7 miles, and breathe air at a pressure of only 3^ lb. per square inch, 

 and still live. And, on the other hand, divers have been down into water 80 feet 

 deep, entailing an extra pressure of about 36 lb. per square inch, and have 

 Teturned safely. One has even been to a depth of 150 feet, but the resulting 

 pressure of 67 lb. per square inch cost him his life.* 



Eecent fasting performances (if the published records are to be trusted) are not 

 less remarkable when we are comparing the human body as a piece of mechanism 

 with those of artificial construction. For what artificial motor could continue its 

 functions forty days and nights without fuel, or, if the material of which it was 

 constructed were gradually consumed to maintain the flow of energy, could after- 

 wards build itself up again to its original substance ? 



These and other performances are, when considered individually and separately, 

 often largely exceeded by other animals specially adapted to their own limited 

 spheres of activity. The marvel is not, therefore, that the human bodily 

 mechanism is capable of any one kind of action, but that, in its various develop- 

 ments, it can do all or any of them, and also carry a mind endowed with far 

 wider powers than any other animal. 



Animals other than man are also adapted for life and movement on or about 

 the surface of the earth. This includes a certain distance below the ground, as in 

 the case of earthworms ; under the water, as in the case of fish ; on the water, as 

 in the case of swimming birds ; and in the air, as with flying birds. 



As far as I know, no animal burrows downwards into the earth to a greater 

 depth than 8 feet,- and then only in dry ground. Man is naturally very ill-adapted 

 for boring into the earth as the earthworm does. Indeed, without mechanical 

 aids he would be helpless in excavating or in dealing with the accumulations of 

 water which are commonly met with underground. But by aid of the steam- 

 engine for pumping, for air-compressing, ventilating, hauling, rock-boring, electric 

 lighting, and so forth, and by the utilisation of explosives, he has obtained a com- 

 plete mastery over the crust of the earth and its mineral contents, down to the 

 depth where, owing to the increase of temperature, the conditions of existence 

 become difficult to maintain. 



1 have said that on land man, unaided by mechanism, has been able to cover 

 about 11|- miles in one hour. Two miles he has been able to run at the rate of 

 nearly 13 miles per hour, and 100 yards at the rate of over 20 miles per hour.* 

 But the horse, though he cannot walk faster than man, nor exceed him in jump- 

 ing heights or distances, can certainly beat him altogether when galloping or 

 trotting. A mile has been galloped in 103 seconds, equal to 35 miles per hour, 

 and has been trotted in 124 seconds, equal to 29 miles per hour.* 



There are many other animals, such as ostriches, greyhounds, antelopes, and 

 solves, which run at great speeds, but reliable records are difficult to obtain, and 

 are scarcely necessary for our present purpose. 



MECHAmCAL AID WITHOUT EXTEANEOTJS MOTIVE-POWEE. 



Let us now consider how man's position as a competitor with other animals in 

 ■•epeed is aff'ected by his iise of mechanical aids, but without any extraneous motive- 

 power. 



Locomotion on Zand. — "Where there is a stretch of good ice, and he is able to 

 liind skates on his feet, he can thereby largely augment his running speed. This 

 was exemplified by the winner of the match for amateurs at Haarlem last winter, 

 who accomplished the distance of 3-1 miles at the rate of about 21 miles per hour. 



' Pall Mall Gazette, July 5, 1893, p. 8. 



- Vegetable Mould, and Earthrvorms, by Charles Darwin, p. 111. 



' Chambers's E'ncyclo2)cFdia, ' Athletic Sports.' 



* Ibid., ' Horse.' 



