Sydney September 6 1870
I have just been appointed Astronomer for New South Wales and am very anxious to possess as soon as I can get it, a good spectroscope suitable for star or comet work. As I have no opportunity here of judging by the performance of different kinds, I have determined to leave it to you to send me what you think will be best only it must be good and one worthy of a public observatory.
My Equatorial was made by Berg?? & Son of Munich has an object glass of 7¼ inches clear aperture?? and a focal length of 10 feet 4 inches. The performance is good and it has a ?? parallel wire micrometer.
I am going to devote myself principally to southern double stars and want the spectroscope to apply to any star comet or other object under observation.
I?? few days since Mr Alherst Le Seur?? who was appointed to work the large reflector at Melbourne was here and he told me that the Equatorial performed better (making allowance for difference in aperture) than the Cambridge 11 in refractor I mention this also that with full aperture it shows two well defined discs with scarcely any radiation when turned on & caucis??: that you may have some idea of its performance to guide you in making the spectroscope.
I cannot send you an adapter for the telescope for I have not one to spare, but we have a good Instrument maker here and I can get that made.
I am prepared to pay £35 or from that to £40 for the spectroscope and hope you will be able to send it to me so as to reach me in January or February next, if before so much the better.
I want you to send me also a glass prism for the same telescope, plane surface 1¼ in unmounted intended for observing the Sun.
I want also to know the prices of your largest glass reflectors equatorially mounted with clock movement from 13 inches upwards.
If you have an agent in Sydney who has written authority to receive money for you please let me know as the government here are very particular about the payment of money.