By Edward Solly, Esq. 



37 



those which would have been obtained, had 10000 or 100000 

 parts of each substance been analysed. The composition of a 

 substance can be expressed as well by whole numbers, as by deci- 

 mals ; whilst the use of the latter frequently leads to confusion. 



The first large experiment was on Savoys. A square of young 

 savoys was taken, the plants in which were as nearly as possible 

 uniform in size, and growing under the same circumstances. They 

 were manured with various saline and inorganic substances, applied 

 as top dressings ; the quantity used increasing gradually from 100 

 to 2000 grains to each plant. The substances taken were, Nitrate 

 of Potash, Alum, Nitrate of Soda, Muriate of Ammonia, Sulphur, 

 Sulphate of Iron, Phosphate of Soda, and Sulphate of Magnesia ; a 

 number of plants being left without any manure, for the sake of 

 comparison. The effects produced by these various substances, 

 on the appearance of the plants were much less than had been an- 

 ticipated ; very slight differences could be observed and those 

 differences which were apparent, were so irregular and uncertain, 

 that it was hardly possible to say how much could fairly be attri- 

 buted to the manures, and how much to local circumstances. A 

 number of the plants were, however, examined chemically, but the 

 result of their examination proved as irregular as the effect produced 

 by the manures. The following table exhibits the proportion of 

 water, organic matter, inorganic substances, and azotised matter 

 which they contained. 



Young white leaves or heart of Savoy ; Composition of 10000 parts. 



