Re: ATM Newton's telescope

["Barlow Pepin" <atmjedit@conceptsnet.com>]

Here are Newton's humble specs in his own words from his book "Opticks."
Read and reflect on our current obsession with precision measures:

"The diameter of the sphere to which the Metal was ground concave was about
24 English Inches, and by consequence the length of the Instrument about six
Inches and a quarter. The Eye-glass was Plano-convex, and the diameter of
the Sphere to which the convex side was ground was about 1/5 of an Inch, or
a little less, and by consequence it magnified between 30 and 40 times. By
another way of measuring I found it magnified 35 times. The concave Metal
bore an Aperture of an Inch and a third part, but the Aperture was limited
not by an Opake Circle, covering the limb of the Metal round about, but be
an opake Circle, placed between the Eyeglass and the Eye, and perforated in
the middle with a little round hole for the Rays to pass through to the Eye.
For this Circle being placed here, stopp'd much of the erroneous Light,
which other wise would have disturbed the Vision. ..."

The figure was spherical, the first corrected mirrors were made later by
Hadley as far as I can tell.



-----Original Message-----
From: Reed Alan Spaulding <shellac@together.net>
To: atm@shore.net <atm@shore.net>
Date: Monday, December 06, 1999 1:57 PM
Subject: ATM Newton's telescope


>
>Does anybody on this wonderful list know where I can find the specs for
>Newtons first reflecting telescope?  I'd like to build a replica of it.
>Thanks.
>
>Nathan Spaulding
>194 Main Street
>Lancaster, NH  03584-1714
>shellac@together.net
>
>