On Vegetalle and Animal Analysis. 63 



oily, or alcoholic^ &c. when the oxygen is in a less pro- 

 portion to tlie hvdroejen than in water. 



ThiruLavv. — Lastly, a vegrtablo substance is neither 

 acid nor resinous, and is analogous to sugar, gum, starch, 

 sugar of milk, to the ligneous fibre, to the crystallizablc 

 principle of manna when the oxygen is in the same pio- 

 portion as in water. 



Thus, supposing for a moment that hydrogen and oxygen 

 were in the state of water in vegetable substances, which wc 

 are far from thinking is the case, the vegetable acids would 

 be formed of carbon, water and oxytjen in various propor- 

 tions. 



The resins, the fixed and volatile oils, alcohol and ether, 

 would be -formed of carbon, water and hydrogen, also iu 

 various proportions. 



Lastly, sugar, gum, starch, sugar of milk, the ligneoMS 

 fibre, the crystallizablc principle of manna, would only be 

 formed of carbon and water, and would only differ in the 

 greater or less quantities which they contained. 



This may be shown by citing various analyses of acid 

 and resinous substances, and of substances which are neither 

 acid nor resinous. 



One hundred parts of oxalic acid contain: 



"Carbon 25-366 



Oxygen and hydrogen 



in the proportions in 



TT J \. ^ .^ [ ti J which they exist in 

 Hydrogen.. 2-743 > 2 < . ' ^^ o- 



■^ «= I r <- ^ water 22-872 



Oxvgen in excess 30-362 



Carbon 26-566"^ 



Oxygen 70-689 



100 J o 



I 



100 



One hundred parts of acetic acid contain : 



f Carbon 50-224 



/-It ,„ ^^.-v Oxvffen and hydrogen 



Carbon.... 30-224^ i. ' '^a {■ °- 



r\ .^ ,^- u in the proportions in 



Oxygen..., 44-147 x; u- u^u • * ■ 



cj A - ^„^ V ti ) which thev exist in 



Hydrogen . , 3-629 V 2 < . ^ ./.„.. 



' ^ " r <- ^ vt^ater 46*91 1 



Oxygen in excess 2-865 



100 J O 



L 



100 

 The oxalic acid contains, therefore, more than half its 



weight of oxygen in excess, in proportion to the hydrogen, 



whereas in the acetic acid this excess is not quite ihrte 



centiemes. 



These two acids occupy the extremes of the series of the 



vegetable acids : of all the acids the one is the most, and 

 Vol. 38. No. 139. July 1811. E th« 



