Dr. Redtenbacher on a Class of Organic Acids. 509 



Calculated. Found. Plcss*. 



18 eqs. Carbon 1350*0 40*75 39-98 40*88 



17 ... Hydrogen. . . . 212*5 6*42 6*33 6*46 



8 ... Oxygen .... 300*0 9*06 9*48 8*89 



1 ... Oxide of silver . . 1450*0 43*77 44*21 43*77 



1 ... Pelargonate of silver 3312*5 100*00 100*00 100*00 



A small quantity of caprylic acid contained in it decreased 

 the carbon and the water, but increased the quantity of oxide 

 of silver. 



9. Capric Acid. — Of all the foregoing acids, the action of 

 nitric acid upon the oily acids produces the smallest quantity 

 of this acid, it being the strongest combination, and contain- 

 ing the smallest quantity of oxygen ; and also from possess- 

 ing the highest boiling-points, during the distillation with the 

 nitric acid and water, the smallest quantity is distilled over. 

 Having dissolved all the barytic salt in water, the first cry- 

 stallization had all the appearance of caprate of baryta. The 

 atomic weight was considerably higher than that of the pe- 

 largonate of baryta, but not so high as that of the caprate 

 of baryta. By means of crystallization, redissolving the first- 

 formed crystals and recrystallizing, I at last raised the atomic 

 weight to 2950 ; but pure caprate of baryta possesses an 

 atomic weight of 2990. Although I had not enough of the 

 substance to submit it to combustion, still there is no doubt 

 that capric acid had been formed. With this is closed the 

 series of the volatile fatty acids, which are obtained by the 

 action of nitric acid upon the oily acids. The largest in quan- 

 tity formed are the caproic, valerianic and acetic acids ; the 

 next in quantity are caprylic, butyric and metacetonic acids ; 

 and the least in quantity formed are the capric, pelargonic 



* H. Pless undertook some time ago the examination of the volatile in- 

 gredients of the plant Pelargonium roseum, (so called from the known 

 scent of the rose), but could not complete it for want of sufficient material. 

 He distilled the plant with water ; the product had the scent of the plant, 

 and an oil swam at the top. The liquid had a sour reaction. It was neu- 

 tralized by baryta water, and the neutral, strongly-scented oil was distilled 

 over. The solution evaporated to dryness contained fatty acids. It was 

 boiled in alcohol, and the first product precipitated by nitrate of silver. 



0284 grm. gave (H 157 grm. silver ; another portion of 0354 grm. gave 

 0*5305 grm. carbonic acid and 0-2058 grm. water. 



The calculation of this analysis is given above under the head of Pless. 

 This is the reason, for want of a better, that I gave it the name pelargonic 

 acid. Respecting the properties of the hydrates of pelargonic acid, I have 

 little to notice, as the quantity of it I possessed was too small. It is an oily, 

 greasy acid, slightly soluble in water, but easily soluble in alcohol and aether. 

 With regard to its other properties, as far as experiments lead, it may be 

 considered to hold a middle place in the hydrates between the capric and 

 caprylic acids. 



