SAMUEL LUTHER DANA. 315 



from time to time, were made by him, and often applied, be- 

 fore their publication by others. 



"The laboratory, in most busy moments, was exceptionally 

 neat ; the deft handling of the apparatus and order of experi- 

 ments expressed the system of thought." 



Soon after removing to Lowell, Dr. Dana became interested 

 in the action of lead upon water, and made a report to the City 

 Council of that city on the danger arising from the use of lead 

 water pipes. His translation and systematic arrangement of 

 the treatise of Tanquerel on Lead Diseases was considered an 

 important contribution to medical knowledge. The discussion 

 of the lead-pipe question gave rise to several pamphlets from 

 Dr. Dana's pen. 



Another division of chemistry in which Dr. Dana did valu- 

 able work was in its applications to agriculture. As the out- 

 come of a comprehensive series of experiments and observa- 

 tions, he published, in 1842, The Farmer's Muck Manual of 

 Manures, which was the sheet anchor of libraries in the rural 

 districts of New England for many years. The next year an 

 Essay on Manures submitted by him won the prize offered by 

 the Massachusetts Agricultural Society. He carried into his 

 agricultural investigations the same scientific methods that he 

 had found so important to success in other technical inquiries, 

 and added an overflowing love for the pursuit in all its varied 

 bearings. The younger Silliman wrote of him : " In point of 

 time, originality, and ability, Dr. Dana stood deservedly 

 first among scientific writers on agriculture in the United 

 States." 



The fourth edition of the Muck Manual was published in 

 1855. Its preface states that " The author is not an agricultur- 

 ist; he does not assume the name even of agricultural chem- 

 ist," and mentions his position at the works of the Merrimac 

 Company. "While pursuing there," it continues, "during the 

 years 1835, 1836, and 1837, researches on the action of cow- 

 dung in calico dyeing, he pushed his inquiries, as a recre- 

 ation, during his few leisure hours, into the nature and 

 action of manures and of soil. Conversation on these 

 matters with the geological surveyor, and with the agri- 

 cultural commissioner of Massachusetts, led to a corre- 

 spondence between the parties, which partly appeared in 

 the published reports on the geology and agriculture of 



