1S8 Account ^ Amici’s Reflecting Microscope. 
quite impossible, on account of the shortness of the focal dig* 
tance in the highest degrees of magnifying power, as the object- 
lens must be brought so near the object as almost to come in 
contact with the huid.^’ 
4. The light may be brought to bear upon all sides, and in 
all directions, even by means of a lamp or a taper, as the flame 
can be brought very near the illuminating mirror, without being 
troublesome to the observer. 
5. As metallic specula do not disperse the light, and conse- 
quently produce no colours, the objects appear of their natural 
colour. 
6. The diameter of the concave mirror being so large, com- 
pared with its focal distance, we may expect so much more dis- 
tinctness. 
7. As the distinctness of the image produced by reflection 
is greater than that produced by refraction, the degree of magni- 
fying power may be carried much higher. 
We must not omit to mention, that Professor Amici has con- 
trived, by a very ingenious arrangement, to convert his micro- 
scope into a species of camera luclda^ in order to enable the ob- 
server conveniently and very exactly to delineate the object, in 
any degree of magnitude, at pleasure. This circumstance un- 
doubtedly enhances the value of the invention. 
Art. XXVI . — Account of the Discovery of the Shetland Cod- 
Bank In the Summer of 1818. In a Communication from 
Samuel Hibbert, M. D. M. W. S., &c. 
The certain knowledge that a very extensive Cod-bank ex- 
isted to the west of the Shetland Islands, was the discovery of 
the summer of 1818, and it will form an important epoch in the 
annals of the British fishery. The visit which I paid to Shetland 
last year, for the purpose of examining its geology, comprised a 
period, when, front a mere suspicion of the existence of the 
bank, its reality was as a point of fact established. Aware of 
the importance of the discovery in a national point of view, I 
omitted no opportunity afibrded me to procure every informal 
tion in my power, with regard to its situation, extent, and pro- 
