24 
ADLER. 
faction to this keen observer. He knocked hard and loud at 
the door which leads to knowledge of the soul, for it seemed 
to have been one of the necessities of this great mind that 
it should attempt all the difficult problems which were 
offered to human observation or curiositv. He loved to 
talk with men possessed of positive religious views upon their 
own beliefs and had a deep interest in a Jesuit, or a Jew, or 
a Buddhist, or a Mohammedan, or indeed any man who 
thought he had secured the truth and knew the way of life 
in this world and the world to come. His paper on ‘‘The 
Laws of Nature” is a very significant contribution from this 
point of view. 
He was probably less understood upon his personal side 
than any other. When I came here to live in 1892, I re- 
member that Mr. Goode said to me once that Mr. Langley 
was a very reserved man and a very lonely one, and that 
though it might be difficult to gain his friendship, the effort 
was well worth the making. I do not know that 1 did make 
a conscious effort. In my then position as librarian, I came 
into official contact with him because of his very great in- 
terest in and constant demand for hooks of every nature. 
By chance I found that he was a collector of translations of 
the Arabian Nights, and had read all the editions in English 
and French available. 1 happened to tell him of my own 
interest in the subject, and the fact that as a student I had 
read portions of the Arabian Nights in the original. There 
then began a closer acquaintanceship which, I am proud to 
say, resulted in a friendship which has been to me one of the 
most profoundly valuable and touching experiences of my 
life. He was a very shy man, and greatly feared that he 
might obtrude himself upon others, or that an advance that 
he might make would prove unwelcome. He was also, like 
some other mathematicians and astronomers, at times very 
much abstracted and with a painfully bad memory for 
names, or rather an inability to associate faces and names 
a difficulty which he told me had nothing to do with his 
scientific studies, but was inherited, and belonged to his 
