THE ORIGINAL FORM OF 'NEW MICROSCOPE' OF POWELL & LEALAND
MAKER: POWELL & LEALAND
MODEL: 'NEW MICROSCOPE'
DATED: 1844
SIGNED ON THE ARM: 'Powell & Lealand, Makers, London' and also dated '1844'
THIS PAGE: Fine Focus Mechanism-as viewed from underneath the arm with covering plate removed.
This mechanism of fine focus, used as soon as the second year of production, and found on other examples*, employs a different mechanism to adjust the fine focus than the wedge that was used in the first year(1843). The lever acting on the nosepiece is now activated by a tilting L-shaped piece, the tilt being adjusted by the fine focus knob. It is clear from this change that Powell & Lealand realized the wedge-type was unsatisfactory as it would require constant re-lubrication to work smoothly. It is also clear from the way that this one is made, that the original lever part was used, but modified by cutting one end off, and soldering it under the remaining piece closer to the middle of that part. This illustrates P & L's efforts to improve, and eventually perfect their design. The final version, simply had the adjusting knob in a vertical position, acting directly on the lever. See the
fine focus comparison page showing the fine focus mechanisms of this microscope as well as the earlier version from 1843.
*Solliday, James L. Personal communication. Mr Solliday reports he has seen this mechanism used in other examples of these early P & L microscopes.
