120 ELEMENTS OF MTCROSCOPY. 



not, after all, direct expressions of the mind of a beauty-loving 

 Creator. The rocks reveal their structure to the searching eye of 

 his magic tube, with the forms of life they enclosed ages before 

 man made his appearance upon the globe, and, in short, there is 

 hardly a realm of nature, organic or inorganic, in which he may 

 not find opportunities for study and research. Moreover, the 

 applications of microscopy in business and everyday life are daily 

 increasing in number, and where one microscopist was to be found 

 twenty years ago, there are now twenty, and to many of whom 

 the microscope is a means of earning their daily bread, whilst to 

 very many more it is a source of constant pleasure, and mental, if 

 not pecuniary profit. Of the latter class, probably only a 

 minority take up any special line of study, and a still smaller 

 number any original branch of investigation, but even to those 

 who use it merely to gratify curiosity, or a love of beauty, there 

 come lessons which, if rightly learned, are fraught with benefits, 

 even if they be only those of neatness and accuracy in working, 

 which microscopy is almost certain to engender. 



Nor, as already said, is it essential to success, that the worker 

 should be provided with all the latest, highest, and most expensive 

 developments of the skill of the optician and mathematician work- 

 ing in conjunction; a steady stand, with good lenses of one-inch 

 and one-quarter inch focal length, will enable him to do all ordinary 

 and much special work, and such a microscope may now be 

 purchased at a price which brings it within the reach of all. 



Our purpose, in this and succeeding papers, will be to show 

 how such stands may be used to the best advantage. We shall 

 take, first, a fairly good stand, of which class Baker's new Nelson 

 model may be taken as the best representative ; and then a cheaper 

 stand, such as the Leitz model, or one of the ordinary English 

 students' stands. 



The essential features of a microscope, apart from the lenses — 

 of which more hereafter — are the stand, tube, stage, focussing 

 arrangements, and means of procuring illumination. 



It is now generally admitted that the freedom from rocking, 

 given by the tripod stand, entitles it to preference over all others, 

 though to this must be added, that unless the triangle included 

 between the feet be of sufficient area, there is much risk of over- 



