1T4 



THE AMERICAN MONTHLY 



[September, 



rence in their cost. But he was eye- 

 ful to add that, in his opinion, the 

 general excellence of the objectives 

 was not indicated by such an examin- 

 ation. 



o 



About Microscope-Stands.-^AI- 

 though it must be generally admitted 

 that the microscopes now made are, 

 mechanically, excellent, and well 

 adapted to the demands of the trade, 

 and while it is not our intention to 

 enter upon a lengthy critique of the 

 various designs, a few words of sug- 

 gestion at this time may not come 

 amiss to both manufacturers and pur- 

 chasers. There are, infact,but veryfew 

 stands in the market which, in design, 

 are equal to what we are yet to see 

 offered for the same or even lower 

 prices. No doubt the reason for this 

 is that the makers are not usually 

 themselves engaged in microscopical 

 work, and, therefore, they can only 

 act upon the often conflicting opinions 

 of those who are. We propose to 

 write a few words about stands now, 

 and next month to add a few sugges- 

 tions about accessories. 



There can be no doubt that the 

 time of large and costly microscopes 

 is passed. Indeed, there will always 

 be some persons who will want them, 

 but the experienced worker, whether 

 he be an amateur or a professional 

 man, will surely discard them. Solid- 

 ity and steadiness can be secured 

 without excessive weight, and the 

 smaller and the more compact a stand 

 can be made, without sacrificing con- 

 venience of manipulation and effect- 

 tiveness, the better it is. Now, 

 a stand that is sixteen or eighteen 

 inches in height is very inconvenient 

 to work with. It is very showy, and 

 doubtless affords the owner great 

 satisfaction to exibit it ; but we will 

 venture the assertion that if there 

 were no such large stands in the 

 country, there would be more original 

 microscopical work done. It is an 

 undeniable fact, which will be admitted 

 by every investigator who has used 

 both large and small stands, that the 



latter are by far the more convenient. 

 Therefore, we say that the best and 

 most salable stands of the future 

 will be low stands not much higher 

 than the common German model. 

 There seems to be some advantage in 

 having the body-tube large, and there 

 must be sufficient space beneath the 

 stage for the ready use of substage 

 accessories. We regard an indepen- 

 dent substage as almost indispensable, 

 but it is by no means necessary that 

 it should be a swinging substage. In 

 fact, the value of the much-lauded 

 swinging substage is, in our opinion, 

 very questionable, and certainly when 

 the mirror and substage are both 

 mounted upon the same swinging bar, 

 as in most of the instruments now 

 made, we would prefer the stationary 

 substage and the independent mirror. 

 These opinions have been held by us 

 ever since Mr. Bulloch showed us 

 (about the year 1870) one of his first 

 swinging substages, and later expe- 

 rience has only served to confirm 

 them. The same opinion has lately 

 been expressed before the Royal Mi- 

 croscopical Society of London, and 

 while there are some differences of 

 opinion, we think it will be difficult 

 to prove that the swinging substage 

 possesses any considerable value. We 

 willingly admit that if it can be moved 

 independently of the mirror it may 

 prove to be convenient and useful, 

 but when it is fixed to the mirror-bar 

 its usefulness is very problematical. 

 It need scarcely be said that we re- 

 gret that our opinions in this matter 

 should be so greatly at variance with 

 those which have guided our manu- 

 facturers of microscopes in designing 

 their best stands; but they are founded 

 upon practical experience, and not 

 wholly upon a priori grounds. In 

 thus freely giving expression to them, 

 we are actuated by no spirit of critic- 

 ism, nor do we imply any invidious 

 comparisons, but we consider that 

 the interests of both makers and pur- 

 chasers would be advanced by an 

 impartial examination of this subject, 

 and by a willingness, on the part of 



