I N G E N E R A L. ig 



formation of a fingle grain of fea-falt that is per- 

 ceptible by our fenfes, an equal number of fimi- 

 lar organic particles are requifue to produce one 

 of thofe numberlefs germs contained in an elm, 

 or in a polypus. A cube of fea-falt muft be dif- 

 folved before we can difcover, by means of 

 cryftalilzation, the minute cubes of which it is 

 compofed : In the fame manner, the parts of an 

 elm or of a polypus muft be feparated, before we 

 can recognife, by means of vegetation, or ex- 

 panfion, the fmall elms or polypi contained in 

 the different parts of thefe bodies. 



The difficulty of affenting to this idea proceeds 

 from the well known prejudice, that we can on- 

 ly judge of the compound by the fimple ; 

 that, to difcover*the organic ftrudure of any 

 being, it muft firft be reduced to its fimple and 

 unorganic parts ; and that hence it is more eafy 

 to conceive how a cube muft necelfarily be com- 

 pofed of other cubes, than how a polypus can 

 be compofed of other polypi. But, if we ex- 

 amine attentively what is meant by fimple and 

 compound, we fhall find, that in this, as in every 

 thing elfe, tlie plan of Nature is very difleren!: 

 from the groffnefs and imperfediion of our con- 

 ceptions. 



Our fenfes, it is Vv^ell known, convey not to 

 us exacft rcprefentations of external objecls. 

 When we v/ant to calculate, to judge, to com- 

 pare, to weigh, to mcafure, &c. we are cbliged 

 to have recourfe to foreign aid, to rules, to prin- 



B 2 ciplctj, 



