1782 Visit of John Play fair 159 



Benvie in Forfarshire, and was known at the Universities 

 of St. Andrews and Edinburgh as an accomplished mathe- 

 matician. His interest in physical researches led him 

 in 1774 to visit Dr. Maskelyne on the mountain Schiehallion 

 in Perthshire, and to share in the labours of that philosopher 

 who was there engaged in his classical experiments on the 

 deflection of the plumb-line. A life-long friendship was 

 there formed between the distinguished Astronomer-Royal 

 and the quiet country clergyman. It happened that in 

 the early part of the year 1782 Playfair was able to spend 

 some months in London, where his first care was to wait 

 on Dr. Maskelyne, who introduced him into the scientific 

 circles of London. He had already published some mathe- 

 matical papers ; but it was not until some years later, after 

 he had resigned his living in the Kirk and had become 

 Professor of Mathematics at Edinburgh, that he was engaged 

 with James Hutton in geological excursions in Scotland, and 

 gained that personal acquaintance in the field with the 

 phenomena of geology which enabled him to grasp the 

 bearings of Hutton's conclusions, and to write that master- 

 piece of scientific disquisition, his " Illustrations of the 

 Huttonian Theory of the Earth," which did so much to place 

 modern physical geology on a sound basis. The intimate 

 friend of Hutton, Joseph Black and James Hall, he was a 

 singularly genial and universally esteemed member of the 

 remarkable group of men who at this time held up the lamp 

 of science in Scotland. 1 After his return to the north from 

 this visit to London he wrote an account of what he had 

 seen, from which an extract descriptive of his experience of 

 the Royal Society Club may be appropriately given here. 



" I was carried by Dr. Solander to dine with the Club of the Royal 

 Society at the ' Crown and Anchor.' Though I met here with 

 many people whom I wished much to see, yet I could not help re- 

 marking that there was little pains taken to make the company 

 very agreeable to a stranger ; and I had occasion to pity two or 

 three foreigners that I saw there, who, as well as myself, had some- 

 times less attention paid to them than their situation required. 



x lt was when Playfair became, in 1783, mathematical professor in 

 Edinburgh University that he joined this group of eminent men. 



