Sir Humphry Davy. 2o^ 



those pigments which have retained their h-eshness and brilliancy 

 through so many centuries. By such means, the artist is taught how 

 to prepare for himself the azure of Egypt and the purple of Tyre. 

 The manuscripts found in the ruins of Herculaneum, originally 1696 

 in number,* excited the hopes of the scholar, that could some 

 method be devised for unrolling them, we should find many of those 

 works of the ancients, (as the deficient parts of Aristotle or of Livy) 

 the loss of which is so deeply deplored. Sir Humphry had made a 

 few experiments on certain fragments of papyri while in England in 

 1818, which encouraged the belief that chemical agents might be 

 found, which could be so applied to the manuscripts, as to separate 

 their folds without destroying their texture. Lord Liverpool, Lord 

 Casdereagh, and even the Prince Regent, afforded ample means for 

 defraying the expenses of such an undertaking ; and the experiments 

 were prosecuted for two months upon the MSS. belonging to the 

 Museum at Naples. During this period he succeeded in partially 

 unrolling twenty-three MSS., and he examined about one hundred 

 and twenty more which afforded no hopes of success. In addition 

 to the labor, in itself difficult and unpleasant, he had to encounter un- 

 expected obstacles thrown in his way by the jealous superintendants 

 of the Museum ; and he was therefore induced to abandon fhe un- 

 dertaking, before he had fulfilled the anticipations he had inspired. 

 The enterprize, however, does not appear to have been entirely abor- 

 tive. Its results threw some fight upon the character of this collec- 

 tion of manuscripts, and upon the modes of writing employed by the 

 ancients. 



The volcano of Vesuvius presented an object to his curiosity 

 unembarrassed by any impediments of human jealousy. It was 

 the more interesting to our philosophic observer, because it af- 

 forded pecufiar facifities for comparing its phenomena with a conjec- 

 ture he had thrown out in a paper on the decomposition of the earths, 

 pubHshed in the Philosophical Transactions in 1812, that the metals 

 of the alkalies and earths might exist in the interior of the globe ; 

 and on being exposed to the action of air and water, give rise to vol- 

 canic fires. The facts as observed at Vesuvius, appeared to strength- 

 en this supposition, and the opinion is evidently gaining ground among 

 geologists. f 



^Phil. Trans. 1S21. 



I See " Outline of the Course ot" Geological Lectures " of Professor Silliman, p. 

 115. 



