Universitätsbibliothek Heidelberg Schlesinger, Frank; Wolf, Max [Adr.]: Briefe von Frank Schlesinger an Max Wolf: Brief von Frank Schlesinger von Yale University. Observatory an Max Wolf (15.12.1926)

YALE UNIVERSITY OBSERVATORY
NEW HAVEN, CONNECTICUT

December 15, 1926

ijW

Professor Max Wolf,
Koenigstuhl Observatory,
Heidelberg, Germany.

Dear Professor Wolf:

I was very glad to get your letter of November
25 and I thank you for the expressions of good will that
it contains.

I have no drawing at hand of the Johannesburg
clock, but I am having some blueprints made of the clock
for the Allegheny telescope, which is like the Johannesburg
clock in every essential. You need not return these blue-
prints to me. You will get them about a week after you
receive this letter.

In testing these driving clocks, I have found
it useful to put a break-contact on one of the rapidly
moving gears and then to record the times that these con-
tacts a're broken on a Chronograph, which of course should
Show also the seconds from a good astronomical clock in
the same Circuit. In this way you can detect the presence
of any error, and the period of this error will enable you
to locate promptly where to look for it among the clock
gears.

A few weeks ago I had the pleasure of meeting
your son at Cambridge, where I understand he is studying
for a year. He is a fine young fellow and you have reason
to be proud of him. I sent you my greetings through him
and I repeat them now.

With kind regards, I am

Very truly yours,