SLATES. 305 



apparent confusion. Their mixture constitutes what 

 may be called the noise of natural laws, and it is the 

 vocation of the man of science to resolve this noise into 

 its components, and thus to detect the underlying 

 music. 



The necessity of this detachment of one force from 

 all other forces is nowhere more strikingly exhibited 

 than in the phenomena of crystallisation. Here, for 

 example, is a solution of common sulphate of soda or 

 Glauber salt. Looking into it mentally, we see the 

 molecules of that liquid, like disciplined squadrons 

 under a governing eye, arranging themselves into bat- 

 talions, gathering round distinct centres, and forming 

 themselves into solid masses, which after a time assume 

 the visible shape of the crystal now held in my hand. 

 I may, like an ignorant meddler wishing to hasten 

 matters, introduce confusion into this order. This may 

 be done by plunging a glass rod into the vessel; the 

 consequent action is not the pure expression of the 

 crystalline forces; t^e molecules rush together with 

 the confusion of an unorganised mob, and not with 

 the steady accuracy of a disciplined host. In this mass 

 of bismuth also we have an example of confused crys- 

 tallisation; but in the crucible behind me a slower 

 process is going on: here there is an architect at work 

 ' who makes no chips, no din/ and who is now building 

 the particles into crystals, similar in shape and struc- 

 ture to those beautiful masses which we see upon the 

 table. By permitting alum to crystallise in this slow 

 way, we obtain these perfect octahedrons; by allowing 

 carbonate of lime to crystallise, nature produces these 

 beautiful rhomboids; when silica crystallises, we have 

 formed these hexagonal prisms capped at the ends by 

 pyramids; by allowing saltpetre to crystallise we have 

 these prismatic masses, and when carbon crystallises, 



