1823.] Hannibal's Passage through the Alps. 197 



this energetic influence to the particles of confined moisture, to 

 apply a quantity of vinegar to the surface of the rock, there 

 would surely be nothing unnatural in his attributing at least a 

 part of the effect to the liquid he employed, particularly when 

 we take into account the very low state of chemical knowledge, 

 in those early ages, even among men of science. 



A phenomenon of annual occurrence in the Polar Seas, bears, 

 I conceive, considerable analogy to the point we have been dis- 

 cussing, and appears to me to confirm the explanation 1 have 

 ventured to advance ; I allude to the frequent disruptions, or 

 icequakes, as they are termed, which take place among the ice- 

 bergs, on the return of the summer season. In those remote 

 latitudes, as soon as the long and dreary winter has passed away, 

 the hot weather sets in with unusual rapidity, in consequence of 

 which the numerous globules of air, that had been incased in 

 those vast accumulations, soon begin to expand,* and struggling, 

 as it were, for liberty, in a short time acquire such irresistible 

 force as to occasion the disseveration of the mountain. In this, 

 way large masses separate, and are precipitated into the ocean 

 with a tremendous noise, not unlike that of a distant peal of 

 thunder. Volcanic eruptions, explosions in coal mines, and 

 several other phenomena, together with the common operation 

 of blasting, might likewise be adduced to prove the wonderful 

 power possessed by elastic fluids, whether in the form of vapour, 

 or of gas, when exposed to high temperature ; but to enlarge 

 upon a principle now so well understood, and so extensively 

 applied, appears altogether unnecessary. 



Article IX. 



On the Presence of Oil in the Serum of the Blood. 

 By Thomas Stewart Traill, MD. 



(To the Editor of the Annals of Philosophy.) 



DEAR SIR, Liverpool, Royal Institution,. Jan. 10, 1823. 



Upwards of two years ago, I detected the presence of a 

 considerable proportion of oil in the serum of the blood of a man 

 labouring under internal inflammation ; and a second attack of 

 decided hepatitis in the same individual afforded me another 

 opportunity of verifying the observation in the spring of 1821. 

 These facts were communicated to the public in the 17th volume 

 of the Edinburgh Medical and Surgical Journal. In both 

 instances, the singularly white colour of the serum induced the 



■* See Leslie on Heat and Moisture. 



