In the most recent printing of "Amateur Telescope Making" by Albert
Ingalls, Willmann-Bell 1996, the Brashear's Process is now found in vol. 3
(3-262). ATM appears to have originally been published in 1937. The
illustrations in ATM, by the way, were masterfully done by Russell W. Porter
who designed and later published many of his sundial ideas in Ingalls SciAm
column, including his 'sun clocks'. The URL's below may prove useful:http://www.willbell.com/tm/tm7.htm http://www.caltech.edu/cgi-bin/arctohtml?30.19-1 A good description of the essentials in the silvering process I found in my copy of "Standard Handbook For Telescope Making" by N.E. Howard, Thomas Y. Crowell Co 1959, page 128. "In essence, it involved making up a solution of silver nitrate, changing the silver nitrate into silver oxide by the addition of ammonia water and potassium hydroxide, and then removing the oxygen from the silver oxide by the use of a reducing agent such as dextrose. The mirror was placed face up in the solution, and when the reducing agent was added, the liberated silver was deposited on the face of the mirror." Regards, Luke Coletti Tony Moss wrote: > Many years ago I silvered my home made telescope mirror using a recipe > containing silver nitrate and sugar I seem to remember. It was called > 'Brayshear's Process' or something similar? They use more durable > aluminium for this purpose these days so it isn't mentioned in anything > printed more recently. > > The recipe came from a small book on telescope making which must have > been written in the 50's but the title and author are long forgotten. > > Does anyone have a copy of the recipe and details of the procedure? I > need to make a half-silvered semi-transparent mirror and this would be > ideal. I remember that it half-silvered everything it came in contact > with and I had black fingers for weeks!
