BIOGRAPHICAL INTRODUCTION xxxiii 



shock, and it was some years before he was able to resume 

 his studies. During this interval he in 1838 paid a visit to St 

 Petersburg. In the autumn of 1838 he became a student at the 

 University of Glasgow ; here he devoted nearly a year to the 

 study of analytical chemistry in the laboratory of Prof. Thomas 

 Thomson. Materia-Medica was studied under Dr J. Couper, 

 and botany under Sir W. J. Hooker. He came to London in 

 the autumn of 1839, and continued his studies at University 

 College, where he attended the chemical lectures and practical 

 classes of Prof. T. Graham, and worked for a short time in the 

 laboratory of Prof. Anthony Todd Thomson. He also studied 

 natural philosophy under J. Sylvester, anatomy under Dr 

 Grant, and botany under Lindley at Chiswick, and made some 

 progress in the German language. In 1840 he went to 

 Germany, and spent a summer session at Giessen, in the 

 laboratory of Prof. Liebig. Here he took the degree of Ph.D. ; 

 two other English students, J. Stenhouse and L. Playfair, after- 

 wards to become celebrated as chemists, took their degrees 

 at the same time. On returning to England, Dr Gilbert 

 renewed his studies at University College, and became class 

 and laboratory assistant to Prof. A. T. Thomson during the 

 winter and summer sessions of 1840-41. In 1842 he left 

 London and became consulting chemist to Mr Burd, a calico- 

 printer in the neighbourhood of Manchester. The turning 

 point of his life soon arrived. Mr Lawes had already made 

 his acquaintance in the laboratory of Prof. A. T. Thomson, and 

 being in want of a trained chemist to assist in the agricultural 

 investigations he had commenced at Rothamsted, he, on the 

 recommendation of Prof. Thomson, engaged the services of Dr 

 Gilbert. On June 1, 1843, Dr Gilbert entered on his work at 

 Rothamsted. The connection between Lawes and Gilbert thus 

 commenced continued till the death of Sir John Lawes in 1900, 

 a period of fifty- seven years. 



The rapid development of the agricultural investigations at 

 Rothamsted after the year 1 843 has been already noticed in the 

 preceding account of the life of Sir John Lawes. The value of 



