THE DYNAMIC ELEMENT IN LIFE. 121 



call brute matter, cannot in the last resort be understood in 

 their genesis. Were it not that familiarity blinds us, the fall 

 of a stone would afford matter for wonder. Neither Newton 

 nor anyone since his day has been able to conceive how the 

 molecules of matter in the stone are affected not only by the 

 molecules of matter in the adjacent part of the Earth but by 

 those forming parts of its mass 8,000 miles off which 

 severally exercise their influence without impediment from 

 intervening molecules; and still less has there been any con- 

 ceivable interpretation of the mode in which every molecule 

 of matter in the Sun, 92 millions of miles away, has a share 

 in controlling the movements of the Earth. What goes on 

 in the space between a magnet and the piece of iron drawn 

 towards it, or how on repeatedly passing a magnet along a 

 steel needle this, by some change of molecular state as we 

 must suppose, becomes itself a magnet and when balanced 

 places its poles in fixed directions, we do not know. And 

 still less can we fathom the physical process by which an 

 ordered series of electric pulses sent through a telegraph 

 wire may be made to excite a corresponding series of pulses 

 in a parallel wire many miles off. 



Turn to another class of cases. Consider the action of a 

 surface of glass struck by a cathode current and which there- 

 upon generates an order of rays able to pass through solid 

 matters impermeable to light. Or contemplate the power 

 possessed by uranium and other metals of emitting rays im- 

 perceptible by our eyes as light but which yet, in what 

 appears to us absolute darkness, will, if passed through a 

 camera, produce photographs. Even the actions of one kind 

 of matter on another are sufficiently remarkable. Here is a 

 mass of gold which, after the addition of l-500th part of 

 bismuth, has only l-28th of the tensile strength it previously 

 had; and here is a mass of brass, ordinarily ductile and 

 malleable, but which, on the addition of l-10,000th part of 

 antimony, loses its character. More remarkable still are the 

 influences of certain medicines. One-hundredth of a grain 



