Intelligence and Miscellaneous Articles. ] 53 



" Having experimented with solutions of nitrate of ammonia, ni- 

 trate of potash, nitrate of soda, bichromate of potash, &c. &c., for 

 the purpose of increasing the explosive properties of this interesting 

 substance, I can affirm that none of the results will bear the slight- 

 est comparison with those obtained from the solution of chlorate of 

 potash, either in rapidity of ignition or in intensity of flame. The 

 process adopted for preparing the inclosed specimens was as follows : 

 viz. into a mixture of equal measures of strong nitrous acid and of 

 oil of vitriol, spec. grav. 1*845, the cotton was immersed and stirred 

 with a glass rod during about three minutes : it was then well- 

 washed in many waters and dried ; a portion of it was then soaked 

 for a few minutes in a saturated solution of chlorate of potash, well- 

 squeezed and dried." 



ON BALSAM OF TOLU, AND SOME PRODUCTS DERIVED FROM IT. 



M. E. Kopp states that the experiments which he has made on 

 this substance confirm the greater number of the results previously 

 obtained. He remarks that the balsam is composed of a very small 

 quantity of tolene C'oH"', C=75H=6"25; of free cinnamic acid, 

 CIS H'6 O* ; of a resin very soluble in alcohol, C^e H?8 O^ ; of a resin 

 slightly soluble in alcohol, C'« H^o O*, or C^e H^o Qio. 



Tolen. — This carburetted hydrogen was prepared by exactly fol- 

 lowing the plan proposed by M. Deville. It is colourless, very fluid, 

 of a penetrating taste somewhat like pepper, and its smell resembles 

 that of elemi. Its density at 60° F. is 0'858 ; its boiling-point is 

 between 310° and 320° F. Exposed in an imperfectly closed tube, 

 it gradually becomes resinous and very slightly coloured. M. De- 

 ville gives as its formula C'^H'^. M. Kopp states that his analysis, 

 which diff'ers but little from that of M. Deville, indicates 0'° H'^, 



Cinnamic Acid. — The free acid of balsam of Tolu, as observed by 

 M. Fremy, is merely cinnamic acid. This fact was proved by ana- 

 lysis, and by its conversion into nitrocinnamic acid, very slightly 

 soluble in cold alcohol ; whereas benzoic and nitrobenzoic acids are 

 very soluble in it. The results obtained by M. Deville are probably 

 derived from his having examined the acids procured by the distilla- 

 tion of the balsam, or extracted by concentrated alkaline solutions. 



M. Kopp has shown that, under these two circumstances, the resins 

 of balsam of Tolu are so changed as to give rise to a large proportion 

 of benzoic acid. The resins, cautiously distilled with caustic soda, yield 

 pure benzoen, and a coaly residue which contains much benzoate of 

 soda. Cinnamic acid, mixed with cold concentrated caustic soda, 

 and submitted to a current of chlorine, is converted into chlorocin- 

 namic acid C'** (H^* Cl^) O*. If however the temperature be raised 

 and the action is very strong, the chlorinated oil described by Mr. 

 Stenhouse is disengaged, and chlorobenzoic acid, C* (H'o Cl^) O*, is 

 formed. 



These two acids strongly resemble each other ; but the latter is 

 more soluble in water and in alcohol, and its salts crystallize more 

 readily. Cinnamic acid, treated with concentrated nitric acid, is at 



