l8 THE HORSE IN MOTION. 



matter is subject to physical laws like other matter: it is attracted 

 by the earth, and will fall with a force as great as if it were inanimate, 

 and is equally subject to the law of falling bodies; it acquires mo- 

 mentum, and its momentum is equal to the weight multiplied by 

 the velocity, the same as that of a railway-car, or a cannon-shot ; 

 and when vitality leaves it, it is resolved to its original elements, 

 oxygen, carbon, etc., which the chemist can prove by analysis. But 

 has the most skilful chemist ever been able by synthesis to restore 

 the lost element, the vital spark? Has he ever been able to imitate 

 the products of that vital laboratory the stomach, and. form the 

 aliment that replenishes the blood? 



With all the knowledge of physics ever acquired by man, can he 

 make a pump so perfect as the heart, — that organ that forces the 

 blood loaded with fresh sustenance to every part of the body ? And 

 what does he know of that power that has kept it in alternate action 

 and rest every instant since before the earliest memories of his child- 

 hood ? 



He has been familiar with the laws of optics for centuries, and has 

 made instruments of glass and metal, in imperfect imitation of the eye 

 of an animal, to exalt the powers of his own vision ; but what would 

 not an optician give to be able to construct a concentric achromatic 

 lens, with automatic power to adapt itself to the distance of objects, 

 such as the eye of the lowest of the vertebrates ? 



Acoustics is another of the physical sciences of which man is a pro- 

 fessor, and he has just invented an instrument by means of which he 

 can communicate in ordinary vocal sounds to a person miles distant. 

 He has recently invented another, by which he can register and pre- 

 serve the intonations of his voice to be returned to him at will at any 

 future time ; but that most wonderful instrument, the ear, he can only 

 wonder at and admire. Without it the world would be without music, 

 voice, or sound ; the faculty of speech, our consciousness, memory, 

 imagination, affection — but it is needless to multiply this class of 

 facts. In nothing does man show himself to be the creation of an 

 intelligent power more than in his own creative faculty. How great 

 have been his achievements in mechanics ! But what comparison does 



