Manchester Memoirs, Vol. lix. (191 5), No. 11. 33 



The reader will perhaps be tempted to consider the 

 above as an expression of a sentimental idealism which 

 the historian and the economist need not take into 

 account. Does the economist recognise inexhaustible 

 treasures ? Has the historian ever spoken to us of con- 

 quests accomplished without the sword ? And have not 

 men remained the same for centuries? Is not the im- 

 provement of man an unrealisable dream ? 



Nevertheless, we have adhered strictly to the truth, 

 in proof whereof let us examine a little more closely this 

 force which conquers truth. 



The eminent men of whom we have made mention 

 were endowed with powerful imaginations, guided by ob- 

 servation and experience, and tempered by the inflexible 

 logic of the mathematical spirit. They endeavoured to 

 give a material form to their ideas. It is only very rarely 

 that their discoveries and their inventions have been due 

 to accident. Almost always a long period of preparatory 

 work has been necessary. 



We see, for example, Archimedes acquiring vast 

 knowledge at the school of Alexandria, after having 

 doubtless received lessons from his father, who was a 

 man of science. We find him improving and extending 

 the work of. the geometricians who had preceded him, 

 and whose work he had studied. 



We see James Watt studying and reflecting through 

 long years ; we see him indefatigably at work, becoming 

 in turn maker of instruments, geometrician, physicist, 

 chemist ; we see him preceded by a long series of inventors 

 who had step by step made progress the common work. 



Lavoisier was a man of immense erudition, an inde- 

 fatigable worker. We see Pasteur studying literature, 

 and then acquiring general scientific ideas ; finally he 

 studied chemistry, and made in this science remarkable 



