Dr. Goring on Achromatic Microscopes. 417 



angle of 45° : it should revolve at the bottom instead of at 

 the side, as in the common way, that the axis of the ellipse 

 may always present itself in the proper direction : by this 

 arrangement, also, it evidently becomes more manageable. 



As all transparent objects are shown by intercepted light 

 furnished by the said mirror, if it is not of due size or proper 

 shape the pencil at the eye-piece will be mutilated, much in 

 the same manner as if the aperture of the object-glass or me- 

 tal was partly closed. I conceive every stand to be vicious 

 and defective which does not possess the properties I have 

 enumerated ; but none of those now made answer completely 

 to all these indications. There is a very superior kind of 

 Ellis's aquatic single microscope, made by Banks in the 

 Strand, and said to be used and recommended by the great 

 Bauer, which approaches nearer to my ideas of a perfect 

 stand than any thing else I have seen ; indeed, the authority 

 of Bauer must be allowed to be paramount in all matters re- 

 lative to microscopes. I have assumed this as a foundation to 

 work upon, and have endeavoured to remedy what I conceive 

 to be its defects and disabilities, and have adapted it to carry 

 an achromatic body ; an Amician reflector, or single magni- 

 fier, constituting what I should be disposed to call a regular 

 working tool, either for dissection, drawing, or observation, 

 which 1 am pretty confident will be found available on every 

 emergency, and for every purpose to which a microscope can 

 be applied. Should any one coincide with me in my views, 

 as here expressed, and wish to have such a stand as I should 

 myself like to use, he may procure it by applying to T. 

 Cuthbert, 22, Bishop's Walk, near the Palace, Lambeth. 

 This artist is now completing an instrument such as I have 

 described ; the patterns for the casts I made with my own 

 hands, under his direction, and assisted by his advice, in order 

 that every thing may be accommodated exactly to my own 

 peculiar conceits on the subject. 



I trust the time will come when a set of Amician metals, of 

 achromatic object-glasses, and of diamond single lenses, will 

 be all adapted to the stand and apparatus in question (for it 

 is contrived to answer equally well for the whole triad) ; and 

 that thus the separate capacities of each of these gigantic im- 



