late Professor of Practical Astronomy in Glasgow. 281 



discovered the principles of the Solar Microscope, so far as to 

 exhibit to several of his friends, in a dark chamber, the images 

 of small objects enormously magnified, by the sun's rays enter- 

 ing at a hole in the window-shutter, and after several refractions 

 falling upon a white ground within. But Mr WILSON as yet was 

 too far separated from the great world, and had too little expe- 

 rience, for bringing forward to the notice of the public any no- 

 velty of this kind ; and, soon after, a similar combination of 

 glasses, with additional improvements, occurred to Mr LIEBER- 

 KUHN, and was at length received as a very curious enlargement 

 of the optical apparatus. 



It was also, whilst employing himself in such researches, that 

 Mr WILSON proposed to many of his philosophical friends the 

 idea of burning at a great distance, by means of plain mirrors, 

 so situated as to throw the rays of the sun upon the same area, 

 without the smallest knowledge of such a thing ever having been 

 imagined by any person before him. But wanting the means of 

 providing himself with any costly apparatus, the matter was pur- 

 sued no farther ; and it is well known that M. DE BUFFON, some 

 years afterwards, when equally uninformed of what KIRCHER had 

 thought of, hit upon the same conception. In 1747, by a mag- 

 nificent construction far beyond the reach of Mr WILSON'S fi- 

 nances, the French philosopher shewed what might be done in 

 this way, and with such effect, as to render the famous secret 

 imputed to ARCHIMEDES, of setting on fire the Roman galleys, 

 much less apocryphal than it had ever been considered before 

 his time. 



In 1737 Mr WILSON departed from St Andrew's, and, by the 

 advice of his friends, went to London, in order to seek for em- 

 ployment as a young person who had been bred to the medical 

 profession. Soon after his arrival there, he engaged himself with 

 a French refugee, a surgeon and apothecary of good character, 

 who received him into his family, giving him the charge of his shop. 



H n 2 



