724 THE POPULAR SCIENCE MONTHLY. 



the additional fuel required, estimated at three cents per hour, would 

 bring the estimate up to 56 cents per hour. It is probable that a 

 suitable magneto-electric engine would cost less than our estimate. 

 The engine of Mr. M. G. Farmer, of Boston, the celebrated electri- 

 cian, bids fair to play an important part in applications of the electric 

 light. The engines of the ship could doubtless run by suitable at- 

 tachments the magneto-electric engine, and our estimate of one at- 

 tendant would doubtless prove sufficient, with the aid of the ordinary 

 ship-watch. 



When one reflects upon the number of steamships crossing the 

 Atlantic, and the increasing danger of collision, with the feeble lights 

 now in use, one is forced to wonder at the want of agitation of the 

 subject. It is safe to affirm that, had the Yille du Havre been pro- 

 vided with more powerful lights, the fatal collision would not have 

 happened. The loss which the steamship company sufiered by this 

 collision would have furnished their entire fleet with the apparatus for 

 producing the electric light. With a careful watch, a light which cau 

 be seen three miles on a clear night would doubtless prove sufficient. 

 The fog-whistle, with an equally careful watch, can also be made 

 efficient to prevent collisions. But a careful watch cannot always be 

 had ; there are many temj^tations to be careless. Drowsiness, in chilly 

 weather, creeps upon even a conscientious lookout, and a powerful 

 masthead-light would supplement human fallibility. 



AEE AOTMALS AUTOMATONS ?^ 



By Peof. T. H. HUXLEY, LL. D., F. E. S. 



I SHALL go no further back than the seventeenth century, and the 

 observations which I shall have to ofler you will be confined al- 

 most entirely to the biological science of the time between the middle 

 of the seventeenth and middle of the eighteenth centuries. I propose 

 to show what great ideas in biological science took their origin at that 

 time, in what manner the speculations then originated have been de- 

 veloped, and in what relation they stand to what is now understood 

 to be the body of scientific biological truth. The middle of the seven- 

 teenth century is one of the great epochs of biological science. It was 

 at that time that an idea arose that vital phenomena, like all other 

 phenomena of the physical world, are capable of mechanical explana- 

 tion, that they are reducible to law and order, and that the study of 

 biology is an application of the great science of physics and chemis- 

 try. Harvey was the first clearly to explain the mechanism of the 



* An address delivered before the British Association at Belfast, August 25th. 



