CHEMICAL, MEDICAL AND DIETICAL PROPERTIES. 207 



Theine is a substance which crystallizes very beauti- 

 fully, forming white, silk-like crystals containing- an atom 

 of water of crystallization, the specific gravity of which 

 is 1.23 at iC, and the 9 water of crystallization is not 

 altogether evaporated by a temperature of 150. As 

 deposited from aqueous solutions it still contains an atom 

 of water, but as deposited from solutions in alcohol 

 or ether, or when sublimed it is anhydrous. It is 

 much more soluble in hot than cold water or in 

 alcohol or ether, and according to Peligot, one part of 

 theine dissolves in 300 parts ether or in 93 parts water at 

 ordinary temperatures. It is a base of the same class as 

 aniline and urea, that is to say, it will combine with 

 acids yielding crystalline compounds, but never neutral- 

 izing an acid. With chloride of platinum, chloride of 

 gold and corrosive sublimate, the hydrochlorate of theine 

 enters into combination, forming a double salt with each. 

 As will be manifest from its formula C 8 H 10 N 4 O 2 

 theine is one of the most highly nitrogenous substances 

 known to chemists, and connected with this high per- 

 centage of nitrogen (almost double that formed in any other 

 albuminous substance) is its property of yielding an 

 abundance of cyanides when fused with soda lime, 

 which property distinguishes it from a number of organic 

 bases, such as piperine, morphine, quinine and cincho- 

 nine. With the base of cocoa which has received 

 the name of theobromine theine is also closely related, 

 being nothing more than methylated theobromine. 

 Strecker having produced it from theobromine by acting 

 upon a silver derivative with iodide of methyl, in a 

 sealed tube heated at 100. Theine exists in tea, 

 not in the free state, but in the form of tannate of 

 tea, which appears to be dissolved by the excess of 

 tannic acid contained by the tea leaf, and so it 



