A treatise on the construction, proper use, and capabilities of Smith, Beck and Beck's achromatic microscopes

Front matter

Bloomfield jg. TVloore

FRANKLIN INSTITUTE LIBRARY

PHILADELPHIA

Introduction

that superior performance which belongs especially to the English Microscopes.

This treatise is strictly confined to the subjects already mentioned; for although the improvement of the Microscope is intimately connected with much that has been done by its aid, it is impossible in this work to make any satisfactory reference to that wide range of observation which is so continually extending with the increase of the power of the instrument.

In concluding this introduction, the firm of Smith, Beck, and Beck have gratefully to acknowledge the assistance they have received, whilst improving the Microscope, from the suggestions or from the contrivances of many amateurs, and especially from those of the late Mr. George Jackson and Mr. Wenham. But it is not with a simple mention only that any author on the Achromatic Microscope is justified in passing over the name of Mr. Lister, all the manufacturers of the improved instrument in England being indebted to him for that theoretical and practical information at the outset, which has enabled them to advance it to its present state of perfection.

Erom Mr. Lister's designs and suggestions various improvements were made in the arrangement and the appendages of the Microscope; but his attention was especially directed to the object-glasses, for the construction of which he not only determined the principle, but also recommended those combinations of lenses which, either unaltered or with modifications, are adhered to at the present day by the best makers.

INTRODUCTION.

V

Erom consideration for those who were engaged in the manufacture, he abstained from taking credit for these; and various misstatements since published having been allowed to pass without notice, his valuable services have lately been alluded to in a manner most superficial and erroneous.

Upper Holloway, March 1865.