[AZ-Observing] Re: Cross Hair material

The late Walter S. Adams, in his recollection of the early history of 
the Mt. Wilson Observatory (two articles in Publications of the 
Astronomical Society of the Pacific, Vol. 59, 1947), when they still had 
to ascend the mountain via a treacherous narrow path on pack mules, 
mentions that E.E. Barnard was particularly fond of a burro named 
"Pinto", who had exceptionally fine hair in his (short) tail, which made 
excellent cross hairs.  My understanding, from other historical sources, 
is that the Victorian instrument makers kept a Black Widow spider in a 
jar for the purpose, because its fine, strong web strands made good 
cross hairs.  (Nobody seems to have asked either the donkey or the 
spider about extracting these strands.)  I have not tried either of 
these exegencies, but I have made satisfactory, if somewhat coarse, 
cross hairs by extracting and stretching individual strands of fine 
copper wire from stranded lamp cord wire.
Gene Lucas
(17250)

Stan Gorodenski wrote:

>Has anyone tried to make a crosshair eyepiece out of their own hair, in 
>my case gray hair? The name implies a 'hair' and so it seems like it 
>shouldn't be a problem.
>Stan
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