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his first paper on the subject appearing in 1861. In connexion with 

 this subject he has executed a great amount of analytical work, made 

 many experiments in dairy management, given several lectures, and 

 published not a few papers recording existing knowledge, and the 

 numerous results of his own investigations. 



In all his work and publications, the thorough manner in which he 

 sought to elucidate the connexion between practice and science is 

 conspicuous. Many other questions of agricultural interest than 

 those which have been referred to, engaged his attention, such as — 

 the properties of soils in other aspects than those which have been 

 mentioned ; the composition and value of town sewage, and also of 

 earth-closet manure ; the chemistry of sugar-beet ; and the chemistry 

 of drinking-waters. 



From time to time Dr. Yoelcker contributed papers to the Chemical 

 Society, and in some cases he gave the same results in less technical 

 form in the " Journal of the Royal Agricultural Society." Of those 

 communicated to both journals, the one involving by far the largest 

 amount of laboratory investigation, and leading to the most important 

 conclusions, both practical and scientific, related to the composition 

 of the waters -of land- drainage, and to the loss of plant-food 

 thereby. 



He was elected a member of the Chemical Society in 1849 ; was 

 several times a member of the Council of the Society ; and was one of 

 its Vice-Presidents at the time of his death. He was elected a Fellow 

 of the Royal Society in 1870. He was one of the founders, and one 

 of the first Vice-Presidents, of the Institute of Chemistry of Great 

 Britain and Ireland, established in 1877- 



On coming to London in 1863, in addition to his duties as Con- 

 sulting Chemist to the Royal Agricultural Society, Dr. Voelcker 

 c )mmenced private practice as a Consulting Chemist, and very soon 

 acquired considerable repute in this capacity, and gained a very 

 extensive practice, not only in connexion with agriculture, but with 

 many other industries, being frequently called upon to give evidence 

 before Parliamentary Committees or Royal Commissions. 



There can be little doubt that his life was shortened by overwork. 

 On Sunday, December 23, 1883, he had an attack of paralysis, not 

 severe, but such as to indicate that absolute rest was essential for 

 some considerable time; the Council of the Royal Agricultural Society 

 accordingly requested him to devote six months to the restoration of 

 his health. As soon, however, as he felt some recovery of strength, 

 it was impossible to restrain him from returning more or less to his 

 active duties. He had no return of paralysis, but in August, 1884, 

 symptoms of heart disease, with other complications, supervened. 

 From this time he never really rallied, and he died on the morning of 

 December 5. For some weeks he had suffered intensely ; and not 



