Science in Early England. 17 



is only meant to include the principal names. Of Neckam 

 and Bacon I shall have more to say presently; Grosseteste 

 has been favourably noticed by George Boole as having 

 had a glimpse of the principle of least action. Starting 

 with a datum derived from Aristotle, that there is greater 

 union and unity in a straight line than any other, and 

 assuming that all united virtue is more powerful than that 

 which is not united, he deduces that nature, operating in 

 straight lines, operates in the best manner possible. Hence 

 he infers that light travels in straight lines, and gives the 

 law of reflection correctly, but accounts for refraction by 

 hinting that the ray is less weakened by this process than 

 the other. He might have learnt all his optics and more 

 from Euclid and Ptolemy. 



Now quitting the list of authors we may glance at some 

 of their works, taking here and there an extract where the 

 quaintness or interest appears to demand it. 



Amongst the arithmetical problems in vogue, we have 

 the following : " The swallow once invited the snail to 

 dinner ; he lived just one league from the spot, and the 

 snail travelled at the rate of an inch a day. How long 

 would it be before he dined ? " This problem casts an 

 unworthy slur upon the powers of locomotion possessed by 

 the gasteropod, and even upon its intelligence, though it 

 does not specifically say that the swallow's invitation was 

 accepted. Here is another, which has been battered to 

 and fro throughout the centuries, but which is still recog- 

 nisable as an old friend : " Three men and their wives 

 came to the side of a river where they found but one boat, 

 capable of carrying over only two persons at once. All 

 the men were jealous of each other : how must they con- 

 trive so that no one should be left in company with his 

 neighbour's wife ? " A third instance shows that the 

 arithmetical bogey of school books, who, when asked a 

 straightforward question, answers it in the most crooked 



B 



