"I should like to do some work (with Professor Yost) in an attempt to prepare certain
compounds of xenon suggested by theoretical arguments. No doubt your xenon is precious;
if, however, you could lend us 10 cc or so (of not necessarily pure stuff), we would
try to return it to you either as such or in some compound (I hope), and we would
be properly grateful." Linus Pauling. Letter to Fred Allen. September 13, 1932.