26 THE POPULAR SCIENCE MONTHLY. 



is more certain than that the contraction of the sun, from a diameter 

 even many times larger than that of Neptune's orbit to its present 

 dimensions, if such a contraction has actually taken place, has furnished 

 about eighteen million times as much heat as the sun now supplies in 

 a year ; and, therefore, that the sun can not have been emitting heat 

 at the present rate for more than that length of time, if its heat has 

 been generated in this manner. If it could be shown that the sun has 

 been shining as now for a longer time than that, the theory would be 

 refuted ; but, if the hypothesis be true, as it probably is in the main, 

 we are inexorably shut up to the conclusion that the total life of the 

 solar system, from its birth to its death, is included in some such space 

 of time as thirty millions of years : no reasonable allowances for the 

 fall of meteoric matter, based on what we are now able to observe, or 

 for the development of heat by liquefaction, solidification, and chemi- 

 cal combination of dissociated vapors, could raise it to sixty millions. 



At the same time it is, of course, impossible to assert that there 

 has been no catastrophe in the past no collision with some wandering 

 star, endued, as Croll has supposed, like some of those we know of 

 now in the heavens, with a velocity far surpassing that to be acquired 

 by a fall, under the sun's attraction, even from infinity producing a 

 shock which might in a few hours, or moments even, restore the wasted 

 energy of ages. Neither is it wholly safe to assume that there may 

 not be ways of which we yet have no conception, by which the energy 

 apparently lost in space may be returned, and burned-out suns and 

 I'un-down systems restored ; or, if not restored themselves, be made 

 the germs and material of new ones to replace the old. 



But the whole course and tendency of things, so far as science now 

 makes out, points backward to a beginning and forward to an end. 

 The present order of things appears to be limited in either direction 

 by terminal catastrophes, which are veiled in clouds as yet impene- 

 trable. 







EDUCATION AS A HINDKANCE TO MANUAL OCCU- 

 PATIONS.* 



By Professor SILVANUS P. THOMPSON. 



THERE can not be two opinions as to the prejudicial influence ex- 

 erted upon the industrial interests of Great Britain by the unsat- 

 isfactory state into which the question of apprenticeship has been 

 gradually drifting, and out of which it has not yet begun to rise anew. 

 Out of harmony with the necessities and conditions of the times, a relic 

 of days long past, ere the steam-engine, or perhaps even the printing- 



* Extract from an article in the September " Contemporary Review," entitled " The 

 Apprenticeship of the Future." 



