242 



NICOLAUS STENO 



In a similar way I should suppose that by the help of a per- 

 meating fluid those minute drops mutually cohere which have 

 formed in a receiver from the material forced out of a retort. At 

 first they cling together on the inside of the upper part of the 

 receiver, but later, when a number of drops have come together 

 in the upper part of the receiver, they fall down and form glob- 

 ular masses which sometimes cling, with their extremities, to 

 the sides of the receiver, and sometimes join other filaments. 

 Filaments of this kind, which I have sometimes noticed in 

 the humor of the eye, I should believe to consist of globular 

 masses and to have been formed in a similar way, and so, too, 

 should I believe filaments and branches to have been produced 

 in the fluid by accretion from without. 



But however the case may stand concerning these things, 

 in the growth of a crystal, we must take into account two 

 movements: one, the movement whereby it is brought to 

 pass that crystalline matter is added to certain places of the 

 crystal and not to others — a movement which I fancy must be 

 attributed to the attenuated permeating fluid, and is to be il- 

 lustrated by the example of the magnet which I have given ; the 

 other the movement whereby the new crystalline matter added 

 to the crystal is spread forth over the plane — and this movement 

 must be derived from the surrounding fluid, just as, when the 

 iron filings have risen up above the magnet, through the move- 

 p. 44. ment of the air, whatever is struck off from one filing is added 

 to another. To this movement of the surrounding fluid I should 

 attribute the fact that not only in a crystal, but also in many 

 other angular bodies, any given opposite planes are parallel. 



From the arguments presented it might be possible to prove 

 that the efficient cause of the crystal is not extreme cold ; that 

 it is not ashes only, burned out by the force of fire, which turn 

 into glass ; that the force of fire alone is not the producer of 

 glass ; that not all crystals were produced in the beginning of 

 things, but that they are even now being produced from day to 

 day ; that it is not a task beyond man's power to disclose the 



their appearance, and produced many erect aggregates of filings, placed one above another, 

 like little needles ; and as these needles stood erected upon the flat paper, so they would run 

 to and fro, according as the load-stone, which was held underneath, moved one way or the 

 other ; and as soon as that was taken away, all this little stand of pikes would fall again into a 

 confused heap." 



