﻿Chemistry and Physics. 479 



rium monohydrate, Ba(OH) 2 + l aq. 2d. When the hydrates 

 Ca(OH) 2 , Sr(OH) 2 and Ba(OH) 2 + l aq. contain more water than 

 corresponds to these formulas, this excess of water is set free at 

 temperatures above 100° C. solely by the action of the heat, and 

 is then carried away by the current of carbon dioxide gas pre- 

 cisely as it would be in a similar current of an indifferent gas. 

 But now the carbon dioxide becomes by this means moist and 

 reacts upon the monohydrate to form carbonate, the amount of 

 which is proportional to the quantity of water set free. Complete 

 conversion of the hydrate into carbonate does not take place 

 even when the water set free reaches its maximum, as in the case 

 of the crystallized hydrate Sr(OH) 2 + 8 aq. 3d. The use of a 

 current of dry carbon dioxide for the purpose of driving out by 

 the aid of heat the combined water of the alkali-earths and the 

 conversion of these earths completely into carbonates, is not satis- 

 factory as an analytical method. — JBer. Berl. Chem. Ges., xix, 

 1973-1982, July, 1886. G. f. b. 



5. On the /Synthesis of active Conine. — Ladenburg has re- 

 peated his experiments upon the synthesis of conine upon a larger 

 scale and has confirmed his former results. The #-allylpyridine 

 was prepared by heating the carefully purified #-picoline in sealed 

 tubes with paraldehyde to 250°-260° for ten hours. From 1 kilo 

 crude a-picoline, by repeating the process, 380 grams pure ar-pico- 

 line and 45 grams allylpyridine were obtained. Its reduction to 

 ar-propylpiperidine was effected by means of sodium, and yielded 

 nearly the theoretical quantity. The hydrochlorate crystallized in 

 white silky needles permanent in the air and fusing at 203°-205. 

 The base itself shows the closest similarity to conine, agreeing with 

 it in odor and in its behavior to water, in its specific gravity, 

 0*8626 at 0°, and in the properties of its salts, especially the double 

 chlorides of gold and of platinum. To still further establish the 

 identity of these bodies, the author converted the ar-propylpiper- 

 idine into conyrine and observed identically the same fluorescence- 

 in the crude product though the pure substance was free from it. 

 The platinum salt had the same fusing point and the same crystal- 

 line form. The physiological action of ^-propylpiperidine is iden- 

 tical with that of conine as proved by Falck. The author believes 

 that he has established the complete identity of these two sub- 

 stances, and therefore has prepared for the first time by pure 

 synthesis a vegetable alkaloid. — Ber. Berl. Chem. Ges., xix, 

 2578- 2583, October, 1886. g. r. b, 



6. On the Identity of Cadaverbie with Pentamethylenediamine. 

 — Ladenburg has succeeded in identifying the base which Brieger 

 discovered a year or more ago in the dead body and which he 

 called cadaverine, with the base recently discovered by himself 

 and called pentamethylenediamine. The two bases have the 

 same boiling point, the same solubility and the same odor. The 

 mercury double salt, however, obtained from pentamethylene- 

 diamine hydrochlorate by mixing its solution with one of mer- 

 curic chloride, forms crystals having the formula C 5 H 14 N 2 (HC1) 2 



