THE LINEAR FORCE OF GROWING CRYSTALS 



285 



mediately successful, so that after a few hours a measurable 

 rise in the glass plate was detected. 



Having established in principle that a considerable load could 

 thus be raised, the attempt was made to develop well formed 

 crystals of alum and to measure the load which they were ca- 

 pable of raising per unit of lifting area. After the technique of 

 these experiments had been mastered, it was found practicable 



c. 



s) k 



Fig. I. 



in a saturated solution of constant temperature to grow clear 

 crystals a centimeter in diameter which would raise a weight of 

 a kilogram through a distance of several tenths of a millimeter. 

 The crystal was placed upon a piece of plate glass in a beaker 

 containing saturated solution of the same material, and loaded 

 as desired. Knowing the weight raised, it appeared an ex- 

 ceedingly simple matter to determine the force required, since 

 it was only necessary to ascertain the actual area of contact be- 



