390 Intelligence mid Miscellaneous Articles, 



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density is 1*043. Its boiling heat is above 266° Fahr., and the au- 

 thor's thermometers did not go higher than this. It readily inflames, 

 and burns with a sooty flame. 



It is not decomposed by passing through a red-hot glass tube. 

 When exposed to the air, or in dry or moist oxygen, it is completely 

 converted into crystallized benzoic acid. Solar light greatly acce- 

 lerates this tranformation, which begins in a few seconds. In the 

 air, and when water and potash are present, benzoate of potash is 

 formed. If these experiments are m#de in a glass tube over mer- 

 cury, the ascent of the mercury indicates absorption of oxygen. A 

 third body is produced during the change of oil into benzoic acid. 

 The method in which this oil is purified shows that it is not altered 

 by the anhydrous alkalies ; but the action of their hydrates is alto- 

 gether different : when heated, out of the contact of air, with hy- 

 drate of potash, benzoate of potash is formed and pure hydrogen 

 is disengaged. 



If the oil be mixed with a solution of potash or ammonia in al- 

 cohol, out of the contact of the air, a benzoate is produced, which 

 precipitates in large brilliant crystals as soon as potash is added. 

 When water is added, the salt is dissolved, and an oleaginous body 

 is separated, different from oil of almonds. 



The oil of bitter almonds dissolves, unchanged, in the concen- 

 trated nitric and sulphuric acids: when the latter solution is headed 

 it becomes purplish red, then blackens, and carbon is disengaged. 

 Chlorine and bromine form new compounds with this oil. Analysed 

 by means of peroxide of copper, the oil is stated to be composed 

 of, foreign atomic weights being adopted, 



14 atoms of carbon 1070*118 79*56 



12 atoms of hydrogen .. .. 74*877 .... 5\56 

 2 atoms of oxygen 200*000 14*88 



1344*995 100-00 



According to the composition of this oil, the formation of ben- 

 zoic acid cannot be explained [but ?] by the mere absorption of 

 oxygen, for during this change, no other product is found. As ac- 

 cording to Berzelius, benzoic acid contains 15 atoms of carbon, 

 12 atoms of hydrogen, and 3 atoms of oxygen, MM. Wohler and 

 Liebig resolved to repeat the analysis of benzoic acid, both cry- 

 stallized and combined with a base. 



The acid was obtained from the resin which furnishes it, and also 

 from oil of almonds • the acid was fused and then burnt with oxide 

 of copper. It was found to consist of 



14 atoms of carbon 107*01 18 6925 



1 2 atoms of hydrogen 7*4877 4*86 



4 atoms of oxygen 40 0000 25*89 



154*4995 100*00 



As the results differ from those of Berzelius, benzoate of silver 

 was analysed. It was prepared by precipitating neutral nitrate of 

 silver by an alkaline benzoate. The precipitate is soluble in a large 



