30 MEMOIR OF DR. WALKER. 



height of the distant lands. Nothing else could 

 render the Isle of Skye and the Isle of Man at tne 

 same time visible. At three such views, the naked 

 eye might extend from the one extremity of Britain 

 to the other. To stretch the eye over so many dif- 

 ferent seas, over such a multitude of islands, and 

 such various countries in different kingdoms, is per- 

 haps a scene that can nowhere be beheld in Europe 

 but from the summit of Jura. 



" During the time that our fire was kindling, we 

 constructed a barometer, when the mercury stood 

 at twenty-seven inches and one-tenth. Fahrenheit's 

 mercurial thermometer was then put into the boiling 

 water, in a kettle which had been made for the 

 purpose ; and, after many repeated immersions, was 

 found to stand constantly at two hundred and seven 

 degrees. "We left the summit of the mountain at 

 seven o'clock ; and left it indeed with regret, having 

 been so much delighted. We descended, not with- 

 out some difficulty and danger, upon the west side, 

 where the mountain is very abrupt, and about mid- 

 night arrived upon the Sound of Islay, at the place 

 from which we set out. Here we again repeated 

 our experiments. The same barometrical tube was 

 filled, and at one o'clock in the morning the mercury 

 stood, at the level of the sea, at twenty-nine inches 

 and seven-tenths; the same height precisely at 

 which it stood the preceding morning at seven 

 o'clock. And as the air and weather had been alto- 

 gether serene, without the least perceptible altera- 

 tion during the intermediate time, there was reason 



