Sir Humphry Davy, Bart. 9 



Bakerian lecture of 1806, owed nothing to the labours of 

 these gentlemen, and it would have been in every respect 

 as complete had they never been published ; but had this 

 lecture been suppressed a vast accession of knowledge 

 would have been lost to the world." 



But a short interval elapsed after his installation at the 

 Royal Institution, till, at the request of the managers, he 

 turned his attention to tanning. He set about the investi- 

 gation with proper spirit, probed the subject to the bottom 

 by visiting the lanyards, eliciting information from the 

 workmen,and where their evidence was deficient in reference 

 to the grand object of improving science, he endeavoured 

 to fill up the hiatus by the results of original research. 



The consequences of his labours were published in his 

 ** Account of some Experiments and observations on the 

 constituent parts of certain Astringent vegetables, and on 

 the operation in tanning," in the Philosophical Transactions 

 for 1803. About the same time, he entered upon the study 

 of agricultural chemistry, and gained so much information 

 that he was requested in 1802, to deliver a course of lectures 

 to the board of agriculture " On the connexion of Chemis- 

 try with Vegetable Physiology." His lectures, which were 

 afterwards regularly delivered before the board for ten 

 years, were published under the title of " Elements of 

 Agricultural Chemistry." Several important points were 

 made known in these lectures, and the method pointed out 

 by which agriculture, instead of being a mere random mis- 

 cellany, might become a true science. His application of 

 scientific views to practice is every where obvious in the 

 pages of the work, but is particularly so under the head of 

 manures; " the great object in the application of manure 

 should be to make it afford as much soluble matter as possible 

 to the roots of the plant, and that in a slow and gradual man- 

 ner, so that it may be entirely consumed in forming its 

 sap and organized parts, he connects this with the chemical 

 principles of his theory ; viz , that the fermentation of ma- 

 nures necessary for the solution of these soluble parts 

 should be a regulated process, and as it is connected with 

 decomposition it should be stopped as soon as the end for 

 which it was instituted is attained." It is not meant to be 

 maintained that his views were infallible, but that they 



