328 Biographical Account of Dr. Wilson, [Nov. 



cap. At the other end of the case which environed the stem, 

 there was soldered a tube of brass, wide enough to admit a scale 

 of proper dimensions, before which there was an opening in the 

 tube, aefended by glass. 



The utmost range of the scale he determined by the points, 

 where the thermometer was found to be stationary when the ball 

 and a certain part of the stem were immersed in water, boiling 

 under the greatest variations of pressure which the climate 

 afforded. The interval so found, he subdivided by other obser- 

 vations into degrees, which corresponded to inches of the baro- 

 meter, and which were so denominated upon the scale. 



In the year 1756, the College of Glasgow, upon the death of 

 Dr. Alexander Macfarlane, of Jamaica, a great lover of, and 

 proficient in, the sciences, received a legacy of a valuable collec- 

 tion of astronomical instruments, which that gentleman had 

 got constructed at London by the best artists, and had carried 

 out with him to Jamaica, with a view of cultivating astronomy 

 in that island. The College upon this soon built an Observatory 

 for their reception, which, by medals placed under the founda- 

 tion, was called by the name of their generous benefactor ; and 

 .Mr. Wilson was immediately thought of by the members of the 

 Faculty, as a proper person for taking charge of it, and making 

 the astronomical observations. At this juncture, his Grace 

 Archibald, Duke of Argyle, who had all along continued his 

 patronage to Mr. Wilson, more especially since he had brought 

 the art of letter-founding into Scotland, used his influence with 

 government, and procured his Majesty's presentation, nomi- 

 nating and appointing him Professor of Practical Astronomy and 

 Observer in the College, with an annual salary of fifty pounds, 

 payable out of the Exchequer; and, accordingly, in 1760, he 

 was admitted to this new office by the unanimous and most 

 cordial welcome of all the members of the faculty. 



His two eldest sons, who had by this time entered upon a 

 com se of liberal education, not long after took upon them the 

 further enlargement and improvement of the letter-foundery ; 

 and, before dismissing this topic, it deserves to be mentioned, 

 that Mr. Wilson lived to such an advanced age, as to enjoy in 

 the most feeling manner the reward of his early diligence and 

 excellent example, in seeing the business rising in their hands 

 to the highest reputation, not only in these kingdoms, but in 

 foreign countries. 



In 1763, when upon a visit at St. Andrew's, an honorary 

 degree in medicine was conferred upon him by his Alma Mater. 



Among the objects which now occupied him in the Observa- 

 tory, his former labours towards improving the reflecting tele- 

 scope were resumed, and pursued for a considerable length of 

 time, with a view of obtaining some certain method of giving 

 the parabolic figure to the gre^it speculum. These trials were 



