SKETCH OF SIR JOHN BEN NET LAWES. 695 



prosecuted at Rothamstead, as a practical chemist ; and together they 

 undertook a series of agricultural investigations in the field, the feed- 

 ing-shed, and the laboratory. The laboratory was at first located in 

 an old barn ; but in 1854, when the friends of Mr. Lawes proposed to 

 present hira a service of plate in recognition of their appreciation of 

 his work, he suggested that a new laboratory building would be a 

 more appropriate and enduring as well as useful testimonial, and the 

 money was applied for the purpose of erecting one. 



The place, identified with Mr. Lawes's experiments, Rothamstead, 

 the patrimonial estate of the investigator, is situated some twenty-five 

 miles from London, in Herts, and is easily accessible to visitors from 

 the Harpenden Railway station. The manor-house is described as 

 being a remarkably fine specimen of Old English architecture, while 

 the domain surrounding it contains some magnificent timber, includ- 

 ing an avenue of lindens, which, for size and regularity of dimensions, 

 are perhaps unsurpassed in the south of England. Around the family 

 mansion lie the five hundred acres that form the experimental sta- 

 tion, which is entirely maintained by Sir John. For the benefit of the 

 large number of laborers whose services are required in the manage- 

 ment of the station, Mr. Lawes many years ago formed an allotment 

 club through which small gardens of about an eighth of an acre each 

 can be rented. For this purpose, in 1882, sixteen acres of land had 

 been allocated, and the whole number of allotment gardens then in 

 cultivation was one hundred and seventy-four. The allotment area 

 is furnished with a club-house. 



The scientific discovery, says an English biographer, around which 

 all Mr. Lawes's subsequent work centered was the disprovement of Lie- 

 big's mineral- ash theory. It was generally supposed at the time his 

 experiments were begun that certain saline bodies, so-called mineral 

 constituents, were essential to the growth and development of the 

 plant, and that such substances must be furnished to it by the soil. 

 The necessity of a certain quantity of nitrogen was recognized ; but it 

 was imagined, since wild plants could thrive without any artificial sup- 

 ply of nitrogen, that a sufiicient amount of that element existed in the 

 atmosphere to render it unnecessary to take any steps for increasing 

 the supply. The cardinal discovery made by Mr. Lawes of the abso- 

 lute necessity of the presence of nitrogen in the soil in order to main- 

 tain its fertility was a contradiction of this view, and led to the open- 

 ing of a new field of agricultural investigation. In connection with 

 the belief in the sufficiency of the atmospheric sources of nitrogen, it 

 was supposed that the fertility of a soil might be maintained for an 

 indefinite period if the different mineral constituents carried off by 

 the crop were annually returned in due quantity as mineral manure 

 to the soil. Respecting these two points, and regarding the sources 

 of nitrogen, Mr. Lawes has said : " I maintain that the amount of ni- 

 trogen supplied to our crops from the atmosphere, whether as combined 



