Microscopium polydynamicum : or, a new construction of a microscope, wherein a variety of magnifying powers is communicated to each object-lens / [Benjamin Martin].

  • Martin, Benjamin, 1705-1782
Date:
1771
Catalogue details

Licence: Public Domain Mark

Credit: Microscopium polydynamicum : or, a new construction of a microscope, wherein a variety of magnifying powers is communicated to each object-lens / [Benjamin Martin]. Source: Wellcome Collection.

    14/18 (page 8)
    by 8 is 6,25 ; to which add unity, the Sum is 7,25 ; tbL multiplied by the given focal Diftance of the Lens 0,5, is 3,625 Inches, the Diftance fought. That is, the Tube GHIK being raifed to the Number 3,625 upon the Scale, the Inftrument magnifies the Objedt then juft 50 Times. As all the Noveltyof this Conftrudtion of a Polydynamic Microfcope confifts wholly in the Body-Part (as it is call’d) it is plain, it may beapplied in any of the common Forms of Compound Micr of copes, and with all the fame Ap¬ paratus* < This is the laft Improvement of the Microfcope that I can think of, in relation to its effential Parts; the moft inquifitive and fcrupulous Connoijfeur will by this Con- firudlion have it in his Power to view Objedls every way, by Single Lenfes, or by a Compofition of them ; magni¬ fied in any Degree he pleafes ; and capable of being mea- fured with eafe in all their Dimenfions by a moll exadt Micrometer. In former Tra&s I have (hewn that both Rejlefling and Refrafling Telefcopes, are, in their own Nature, Univer- falPerfpeflives, or may be conftrudfed and adapted to mag-, nify every Sort of Objedls ; butat the fame Time, it muft be confeft, this was done by a Combination of different Mirrors, and Lenfes, in the faid Jnftruments. In the prefent Effay it is propofed to give a further Illuftration of the Simplicity and Univerfallity of Optical Conftruc- tions by an Example of the Application of one and the fame Lens as an Objedt-Glafs in a Telefcope for viewing diftant Bodies on one hand, and in a Microfcope for magnifying all Kinds of fmall Objedls on the other \ and that with various Degrees of Magnifying Power in each Cafe. It is prefumed that no Perfon curious in Optics can be unacquainted with the Patent-Opera conftrudted with 4 Con-