394 Scientific Intelligence. 



formed with mercury which may be distilled in hydrogen at 400°, 

 but which forms nitride when heated in nitrogen. Heated to red- 

 ness with potassium or sodium chloride, calcium sets the metal 

 free. Water acts on calcium only very slowly, evolving hydro- 

 gen. At a red heat, it combines explosively with phosphoric 

 oxide, and decomposes silica, yielding calcium silicide and some 

 silicon. At 600° it reduces boric oxide to boron. Nitric acid 

 when strong acts on calcium very feebly, though when diluted the 

 action is rapid. Fuming sulphuric acid is reduced by the metal. 

 Heated to dull redness in ammonia, a mixture of hydride and 

 nitride is produced. In liquefied ammonia at — 40°, calcium 

 ammonia is formed, a reddish brown solid. — C. P., cxxvii, 584- 

 590, October, 1898. G. f. b. 



4. On New Bases from Strychnine. — It has been noticed by 

 Tafel that when a current of five amperes at a potential of three 

 and a half volts is passed through a solution of 30 grams of 

 strychnine in 180 grams of concentrated sulphuric acid diluted 

 with 120 grams of water, two poisonous bases are produced which 

 he calls tetrahydrostrychnine and strychnidine. After passing 

 the current for two hours, the liquid, diluted with four volumes 

 of water, is nearly neutralized with barium carbonate, filtered, 

 heated to boiling and treated with barium hydrate in slight 

 excess. The strychnidine is contained in the precipitate while 

 the filtrate contains the tetrahydrostrychnine. Strychnidine crys- 

 tallizes from alcohol in stellate groups of colorless needles, 

 fusing in vacuo at 252° and having the structural formula 



^CH 2 

 C 20 H 22 NO^,^ It boils at 290°-295° under 14 mm pressure, and 



may be distilled undecomposed, the distillate solidifying to a crys- 

 talline mass. It is sparingly soluble in water, but dissolves more 

 freely in alcohol, benzene and chloroform. A 6*4 per cent chloro- 

 form solution has a specific rotatory power [a] D — — 8*28° at 20°. 

 Dissolved in sulphuric acid, it gives color with oxidizing agents. 

 Its aqueous solutions with excess of acid become intensely red 

 with potassium dichromate, hydrogen peroxide, ferric chloride 

 and sodium nitrite. Tetrahydrostrychnine C 20 H 22 NO(NH) . CH 2 . 

 OH crystallizes from alcohol in colorless prisms, containing a 

 molecule of the solvent, .which it loses at 100°. It dissolves in 

 280 parts of water at 20°, the solution being strongly alkaline. 

 It resembles strychnidine in its action with sulphuric acid and 

 oxidizing agents, but gives a wine-red solution when its hydro- 

 chloric acid solution is treated with chromic acid or ferric 

 chloride. Strychnoline, obtained by reducing dioxystrychnine in 

 amyl alcohol with sodium, and dihydrostrychnoline, produced by 

 passing a current through a solution of deoxystrychnine in sul- 

 phuric acid, are also described. — Liebicfs Annalen, ccci, 285-348, 

 August, 1898. G. f. b. 



5. A History of Physics in its Elementary Branches including 

 the Evolution of Physical Laboratories ; by Florian Cajoei, 



