474 



OPERATIONS SUBSIDIARY TO INDUCTION. 



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into it as elements. This was done, 

 most skilfully and successfully by the 

 French chemists, though their nomen- 

 clature has become inadequate to the 

 convenient expression of the very com- 

 ])licated compounds now known to 

 chemists. The only thing left imex- 

 pressed by them was the exact pro- 

 portion in which the elements were 

 combined ; and even this, since the 

 establishment of the atomic theory, it 

 lias been found possible to express by a 

 simple adaptation of their phraseology. 

 But where the characters which 

 must be taken into consideration, in 

 order sufficiently to designate the 

 Kind, are too numerous to be all sig- 

 nified in the derivation of the name, 

 and where no one of them is of such 

 preponderant importance as to justify 

 its being singled out to be so indi- 

 cated, we may avail ourselves of a 

 subsidiary resource. Though we can- 

 not indicate the distinctive properties 

 of the Kind, we may indicate its 

 nearest natural affinities, by incor- 

 porating into its name the name of 

 the proximate natural group of which 

 it is one of the species. On this 

 l)rinciple is founded the admirable 

 binary nomenclature of botany and 

 zoology. In this nomenclature the 

 name of every species consists of the 

 name of the genus, or natural group 

 next above it, with a word added to 

 distinguish the particular species. The 

 last portion of the compound name is 

 sometimes taken from some one of the 

 jieculiarities in which that species 

 differs from others of the genus ; as 

 Clematis integrifolia, Potentilla alba, 

 Viola palustris, Artemisia vulgaris; 

 sometimes from a circumstance of an 

 lustorical nature, as Narcissus poeti- 

 cus, Potentilla tormentiUa (indicating 

 that the plant is that which was for- 

 merly known by the latter name), 

 Kxacum Candollii (from the fact that 

 I )e Candolle was its first discoverer) ; 

 :md sometimes the word is purely 

 conventional, as Thlaspi bursapastoris, 

 Kanunculus thora — it is of little con- 

 se<]uence which — since the second, or, 

 as it is usually called, the specific 



inde- 



name, Could at inost express, 

 pendently of convention, no more 

 than a very small portion of the con- 

 notation of the term. But by adding 

 to this the name of the superior genus, 

 we may make the best amends we 

 can for the impossibility of so con- 

 triving the name as to express all the 

 distinctive characters of the Kind. 

 We make it, at all events, express as 

 many of those characters as are com- 

 mon to the proximate natural group 

 in which the Kind is included. If 

 even those common characters are so 

 numerous or so little familiar as to 

 require a further extension of the 

 same resource, we might, instead of a 

 binary, adopt a ternary nomenclature, 

 employing not only the name of the 

 genus, but that of the next natural 

 group in order of generality above the 

 genus, commonly called the Family. 

 This was done in the mineralogical 

 nomenclature proposed by Professor 

 Mohs. " The names framed by him 

 were not composed of two, but of 

 three elements, designating respec- 

 tively the Species, the Genus, and the 

 Order ; thus he has such species as 

 Rhonibohedral Lime Ilaloide, Octohed- 

 ral Fluor Ilaloide, Prismatic Hal 

 Baryte." * The binary construction, 

 howe-^r, has been found sufficient in 

 botany and zoology, the only sciences 

 in which this general principle has 

 hitherto been successfully adopted in 

 the construction of a nomenclature. 



Besides the advantage which this 

 principle of nomenclature possesses, 

 in giving to the names of species the 

 greatest quantity of independent sig- 

 nificance which the circumstances of 

 the case admit of, it answers the fur- 

 ther end of immensely economising the 

 use of names, and preventing an other- 

 wise intolerable burden on the me- 

 mory. When the names of species 

 become extremely numerous, some 

 artifice (as Dr. Whewellf observes) 

 becomes absolutely necessary to make 

 it possible to recollect or apply them. 

 " The known species of plants, for ex- 



* Nov. Org. Renov., p, 274. 

 t nisi. Sc. Id., i. 133. 



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