Microscopic illustrations of living objects, with researches concerning the methods of constructing microscopes, and instructions for using them / [Andrew Pritchard].

  • Andrew Pritchard
Date:
1845
Catalogue details

Licence: Public Domain Mark

Credit: Microscopic illustrations of living objects, with researches concerning the methods of constructing microscopes, and instructions for using them / [Andrew Pritchard]. Source: Wellcome Collection.

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    the vast perfection to which the telescope in more recent times has been brought? I need only mention the dis- covery of the aberration of light; the resolution of nebule and of the double stars ; the motions of these binary systems, and their subservience to the same law of gravitation as governs the solar; the position and direction of the latter in space: —I might mention many others, all equally important—all marvellously grand! And so with respect to the Microscope in aiding to ex- tend our knowledge of the economy of this planet. Every improvement in this instrument has developed some im- portant feature in the structure and design of the almost infinitely varied organized beings of our earth. The achromatic principle, which was at once adapted to the telescope with the most astonishing success, did not produce the same happy result on its first application to the microscope. The recent discovery of Dr. Goring, that the penetration of this instrument was dependent upon the angle of aperture, or the number of rays of light collected by the object-lens from every point on the surface of the object, was requisite for the accomplish- ment of this desirable purpose. By thus applying the achromatic corrections and those for sphericity to this in- strument, it has now been perfected, and elevated to a grade nowise inferior to the telescope. ‘The fruits of this discovery are fast pouring in upon us, and promise to yield a rich and most abundant harvest. We will al- lude cursorily to some of those which have been reaped already ; a few only will suffice to shew their importance,