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John Lawes in the investigation at Rothamsted thus expressed himself on 

 this wonderful peculiarity of the vegetable world: "The immense 

 variety of substances produced in the vegetable kingdom has always 

 been a source of astonishment to the chemist. The plant is indeed the 

 finest chemical laboratory with which we are acquainted. While some 

 kinds of chemical work are common to all plants, there is hardly a 

 species which does not possess some special capabilities, which does not 

 produce some products different from its neighbors. When we survey 

 the whole vegtable kingdom, the extent to which this specialisation is 

 carried, and the immense variety of the products obtained become 

 simply overwhelming. Chemists are still unacquainted with the larger part 

 of the substances produced by plants. When we turn from the pro- 

 ducts of plant work to the materials employed our wonder still increases, 

 for these materials are of the simplest kind water, carbonic acid, 

 oxygen, nitric acid and a few inorganic salts yet out of these the 

 whole of the immense variety of vegetable products is constructed." 



In the interesting lecture by Mr. Shutt to which I have already 

 referred, he traced the travels of oxygen and the manner in which that 

 element carries carbon to the vegetable kingdom, and assists in storing 

 it up in plants in the form of carbohydrates, such as starch and sugar 

 and cellulose. These substances are, however, quite destitute of nitro- 

 gen, and we cannot say much about them now. We are tracing now 

 the fortunes of nitrogen, and that element occupies itself in the plant in 

 building up an entirely different set of compounds from the carbo- 

 hydrates, namely, the albumenoids, or as Beilstein calls them the album- 

 inates, or as Mulder christened them the proteids. In casting round for 

 the word which indicates popularly those of them which occur in the 

 vegetable world, I should be inclined to fix on the word gluten, but 

 that substance is only a mixture of insoluble albumenoids, and it is 

 doubtful as to whether it exists in the original grain. 



No doubt this general name of albumenoids has been conferred 

 upon all these bodies from the resemblance they bear in some of their 

 properties and always in chemical composition to ovalbumenor white of 

 egg. This substance is soluble in water in its natural state and 

 ulates on heating. 



