Gerhard? s Organic Chemistry. 



99 



By this arrangement we are able at once to give a new substance 

 a place, and to determine its relation to other series of compounds ; 

 those bodies which are homologues are always found in the same 

 vertical column, and hence in looking over the table, we see at 

 once in what families homologues of any particular form exist, 

 and how these may be formed from other bodies of the same 

 family. This may be illustrated by an extensive class of homol- 

 ogous acids of the form R0 2 , which are here given with their 

 families and formulas. 



1. Formic, 



2. Acetic, 



C 



H 



C. H 



; H 



H 



3. Metacetonic, C 

 4 Butyric, C^ 



5. Valerianic, C* H* O 



6. Caproic, C 



3 11. 

 0„ 



7. Enanthylic, C 7 



8. Caprylic, C 



9. Pelargonic, C 

 10. Capric, 



3 



9 



C 



I 



H l2 

 H 14 

 H !6 

 H 18 

 H 20 O 



2 



12. Laurie, 



13. Cocinic, 



14. Myristic 



15. 



16. Ethalic, 



17. Mar ear i< 



C 12 H 24 2 

 C I3 H 26 



C I4 H 28 2 



C 



c 



18. Anamiritic, C 



19. Stearic, 



C 



1 



1 7 



1 8 



1 9 



H 

 H 

 H 

 H 



3 2 



3 4 



3 6 



3 3 



o 

 o 

 o 

 o 





acids 



derived 



Spermaceti 



are 



inner laiimies , uui m umyA«* w 4 .■.-■. 8 ^ 7 ***-** ^~~~ 



O, we have bodies corresponding to aldehyde, and 



directly from alcohols of the formula R+-0: and in the 2d we 

 find aldehyde C 2 H 4 O, a derivative of alcohol, which fixes one 

 equivalent of oxygen to form the acid. 



family has the formula C , e H 3 2 O, and forms ethalic acid by 

 combining with an equivalent of oxygen; it is consequently 

 a homologue of aldehyde. No homologues of alcohol 

 known in the other families; but in butyral G 4 H 8 O, and bees- 

 wax G H 



enanthole and menthol are probably the aldehydes of the 7th and 

 10th families. We may anticipate that future researches will 

 discover an aldehyde and alcohol for each of these acids, and fill 

 «P the 11th and 15th families by a similar series. Four acids 

 °f this group have been added to the list within the last two 

 yeais * and butyral was but recently discovered as a product of 

 the destructive distillation of butyrate of lime It will be re- 

 membered that ethal, an alcohol, is formed by the action of pot- 

 ash upon spermaceti its corresponding aldehyde We can thus 

 obtain aldehydes from alcohols and acids, and alcohols from 

 aldehydes. 



the enanthylic or azoleic, 



ic, observed by 

 gnpposed to be 



'The, *,, the me.ucetomr, dweweted by Gottlieb; ifc« ewwttbj 



which was formerly considered as a bibasic acid ; and the pelargorn 

 "Mtenbacher among the products of the oxydation of o»e.c, and —"rr---- -- ■ -- 



^"■■cal with the acid of the pelargonium roseum. This on :. « » jjj Pj c £*£ 

 *«h assigned to the copsic acid ot Chcvreul, which the ob. .rvat.ons ot Lercli 

 h are shown to be a mixture of capric with a new add, the caprylic. 



