i877-j Notices of Books. 2 8 t 
vigour could grasp the whole mass of it, they still depended 
largely upon authority. For that aggregate of knowledge, which 
they were able to grasp, was but book knowledge and not source 
knowledge.” It is hardly too much to say that Mr. Graham had 
grasped, early in his career, all that was then known of chemistry 
and physics. He cared but little for the prevailing theories of his 
time, but for all “ source knowledge ” derived from experiment 
he had the highest respedt. In his first paper (in 1826) he 
alludes to the researches of “ that ingenious chemist Mr. Fara- 
day,” and he constantly quotes the labours of others or makes 
their work a starting-point for fresh discoveries. No man ever 
had a higher reverence for authority or more constantly appealed 
to it. 
