74 On saline combinations 



Art. V. Observations on the existence of Saline combinations in an 

 organized state, in vegetable structures. By Golding Bird, Esq. 

 F.L.S. F.G.S. &c. Lecturer on Experimental Philosophy at Guy's 

 Hospital. 



Botanists have long been familiar with the fact, that vege- 

 tables, during every stage of develop ement, contain certain 

 saline, and, as usually considered, inorganic constituents, dis- 

 solved in their sap, or imprisoned in their tissues ; and the 

 question has long been agitated, whether these saline matters 

 are derived from external sources, or actually formed by the 

 vital chemistry of the vegetable being. The former seems to 

 be the more probable, and is certainly the more generally re- 

 ceived opinion ; since it is obvious that the admission of the 

 latter, would be equivalent to asserting, that all, (chemically 

 speaking) simple substances, as potassium, sodium, &c. are 

 elaborated by plants, from the elements yielded by the earth 

 in which they grow, by the water with which they are sup- 

 plied, or by the aerial medium in which they exist ; and, con- 

 sequently, that all chemical substances are compounded of 

 nitrogen, hydrogen, oxygen, or carbon : a conclusion totally 

 at variance with the received theories of chemistry. 



Upon expressing the fluids contained in any vegetable tis- 

 sue, we find portions of saline matter dissolved in the various 

 secretions; these saline matters being of that class usually 

 denominated inorganic, and incapable of being formed by the 

 vital energy of the plant : but if, after thoroughly washing the 

 vegetable tissue, exhausted of its juices, we digest it in weak 

 acids, until nothing more is yielded up to these solvents, we 

 shall obtain a substance nearly white, composed of cellular 

 or vascular tissue, or both, and forming, in the opinion of 

 many eminent botanists, the vegetable skeleton. Let us now 

 very carefully incinerate this mass of tissue, exhausted of its 

 juices, and apparently also of its saline ingredients, by expos- 

 ing it to heat on a tray of platinum foil, and examine the re- 

 sults. Now as, according to the opinions of some of the first 

 botanists of the day, all principles except hydrogen, oxygen, 

 carbon or nitrogen, are to be regarded as foreign to plants,* 

 and therefore not necessarily, or perhaps possibly, entering, 

 as organizable constituents, into the formation of vegetable 

 structure, we ought to expect to find left on the platinum tray 



* " Those principles are called foreign to plants, which cannot be referred 

 to either hydrogen, oxygen, carbon, or azote ; such, for example, are carbo- 

 nate of soda, sulphate of soda, nitrate of soda, the carbonates of potash, lime, 

 and magnesia, phosphate of lime, chlorides of soda and potash, (query, sodi- 

 um and potassium) and the oxides of aluminum, silicium, iron, and manga- 

 nese ; — &c." Lindley ; — Introduction to Botany, p. 232. 



