158 ELECTRIC VIEW OF MATTER [CH. xvi. 



cannot be maintained electrostatically between two 

 neighbouring metallic surfaces, but they can be 

 momentarily imparted, by a sudden jerk or disruptive 

 discharge or received electric impulse ; and these are 

 the things which are effective in promoting cohesion. 

 In the two diagrams ; fig. 20 represents a couple 

 of atoms with interleaved electrons of opposite sign 



c 



o 



0000 



FIG. 21. Two Polarised Atoms, illustrating electrically intensified 

 cohesion. 



in square order, the atoms being within range of 

 one another and so cohering by molecular or non- 

 chemical forces. They have adjusted themselves into 

 a cohering position ; but a vertical shear through half 

 the distance apart of the electrons would disintegrate 

 them. An angle represented by half the electron- 

 distance divided by the molecular distance, is therefore 

 a measure of the maximum distortion a substance can 

 undergo. 



