On the Colour of the Blood. 203 



produced by a device of a crimson tint; but in more than sixty 

 trials with this and every other variety of colour used in ornament- 

 ing porcelain, the author could observe no such effect as was in- 

 variably produced by patterns of a green tint. The eifect was 

 scarcely apparent, if the pattern was not somewhat elevated. Mere 

 elevation of the porcelain, however, is not the cause of the change 

 of colour. Adhesion of a little oxygen of the air to the surface of 

 the pattern is not its cause ; for no change is produced by the green 

 devices of porcelain on a gelatinous mass of gelatin and protoxide 

 of iron, which is quickly rendered brick-red wherever it is put in 

 contact with oxygen. Neither is the change owing to any peculiar 

 arrangement of the molecules of the blood, because it is produced 

 equally on coagulated blood and upon that which is allowed to coa- 

 gulate in the cup. The author is compelled, therefore, simply to 

 record the fact, that objects on porcelain of a green colour produce 

 their impression, and this with extreme accuracy, on venous blood 

 left in contact with them, and that the change of colour which takes 

 place seems identical with the florid hue occasioned by arterializa- 

 tion of the blood from ordinary causes. 



5. On two Storms which passed over the British Islands in 

 the end of November 1838. By David Milne, Esq. Ad- 

 vocate. 



It was stated, that the first indication of the advent of these two 

 storms to the British islands was given by the barometer. On the 

 25th and 26th November, the barometer in all parts of the United 

 Kingdom began to sink ; and it is important to observe, that, not 

 only when this sinking began, but likewise for nearly two days 

 after, the wind was blowing E. or NE., and was accompanied by 

 a severe frost, circumstances which of themselves cause the mer- 

 curial column to rise. 



The exact hours on the 25th and 26th November at which, in 

 diflferent places, the barometer began to sink were noticed, from 

 which it appeai-ed that the sinking took place in the south part of 

 the United Kingdom about five or six a. m. on the 25th, and in the 

 north of Scotland about two or three in the morning of the 26th. 



I. Now, as the first storm did not reach England, or, in other 

 words, that part of the surface of the globe, till about noon on the 

 26th, and the north part of Scotland till the night of the 27ih or 

 morning of the 28th, it is obvious that the upper regions of the 

 atmosphere were, in the British islands, affected before the lower 

 regions by a period of about thirty hours. It follows, that the 

 upper part of the storm preceded the loiver part, in its progress over 

 the surface of the globe. 



This first storm commenced at Cork on the 26th, at 11 a.m.; 

 at Cornwall, about noon ; at Dublin, about 3^ p. M.; at the Isle of 

 Man, early in the morning of the 27tli ; at Lismore, on the night 

 of the 27th; and Cape Wrath, not till the 28th November. 



The wiud at all these places, on the commencement of the storm, 



