THE BANGOR LABORATORIES. 491 



be in themselves essentially interesting occupa- 

 tions ; but if it becomes necessary to measure 

 something smaller than can be seen with the 

 eye, the measurement itself becomes an object 

 to inspire the worker with interested ardour. 

 Dulness does not exist in science. What do you 

 think of a measurement of something you can 

 only gauge by inference from the performance of 

 the apparatus tested in some peculiarly subtle 

 way ? The difficulties to be overcome in physical 

 science in mere measurement are teeming with 

 interest. Properties of matter, or forces to be 

 contended with, oblige us to be always digressing. 

 We cannot go on saying "We will think of 

 nothing but the object before us." Every person 

 who aims at one object of course perseveres until 

 he attains it ; but he keeps his mind open until he 

 can return to some other object never thought of 

 at first, but which thrust itself on him as a diffi- 

 culty occurring in the pursuit of the first object. 

 The very disappointments in attaining objects 

 sought after in the investigations of physical 

 science arc the richest sources of ultimate profit, 



