132 
Specula . 
As I have now been forced to appear before the public, 
I have hopes I shall be able to prevail on some of my 
friends to commit themselves in the same way, in the con- 
fidence that their labours will be found useful to the 
public..— I am Sir, your’s truly, 
ANDREW THOMSON. 
Banchory , by Aberdeen , May 5th , 1805 . 
[11 JVich. Jour . 125 . 
Observations on the Metallic Composition for the Specula 
of reflecting Telescopes , and the ma?mer of casting 
them : also , a Method of communicating to them any 
particidar Conoidal Figure : with an attempt to ex- 
plain on scientific principles , the grounds of each Pro- 
cess : and occasional remarks on the construction oj 
Telescopes . By the Rev . James Little. 
There are but few things produced by the united effort 
of mechanical artifice and intellectual labour, which have 
done more honor to the ingenuity and invention of man, 
than the reflecting telescope ; which has many advan- 
tages over any of the dioptrical kind, notwithstanding 
their improvement by acromatic glasses. It will bear a 
greater aperture, and may be made to magnify more, (as 
being more distinct,) in proportion to its length, than the 
others, as they are at present made ; and its dimensions 
and powers are unlimited. What its excellence is, espe- 
pecially the Newtonian construction of it, has been prov- 
ed by Dr. Herschell, to his own honor, and that of the age, 
and country, and patronage, which encouraged his labours. 
Accordingly, the persons, eminent for science and me- 
chanical ingenuity, appear to have felt a peculiar and dis- 
interested pleasure, in contributing to its improvement ; 
and the late discovery of a metallic composition for the 
mirrors of it, which will bear as high a polish as glass, 
reflect as much light as glass transmits^ and endure al- 
