212 



THE AMERICAN MONTHLY 



[November, 



with a carefully-made toothed rack. 

 The slow movement, being useless 

 for the slight magnification, has been 

 suppressed. 



The objective is variable ; that is to 

 say, it gives all magnifications com- 

 prised between two limits. This re- 

 sult is obtained by the separation, 

 more or less great, which may be 

 given to the lenses of the system by 

 means of a sliding tube. The image 

 formed by this objective is perfectly 

 aplanatic, quite to the borders of the 

 field, but slightly obscure and milky 

 for the fine details. I presume, how- 

 ever, that this defect is not due to the 

 objective, but in part to the ocular 

 and in part also to the excessive 

 length given to the tube. - 



The ocular, of a diameter superior 

 toT:he ordinary oculars, is constructed 

 to give a large image of the object. 

 The apparent diameter of the field, 

 measured at the distance of 255 mm., 

 by means of a camera lucida, is 200 

 mm. With the ordinary ocular No. 

 I of Nachet the sam"& diameter is 135 

 mm. ; with ocular No. i of Pi'az- 

 mowski it is only no mm. 



EDITORIAL. 



Publisher's Notices. — All communications, re- 

 mittances, exchanges, etc., should be addressed to the 

 Editor, P. O. Box 630, Washington, D. C. 



Remittances should be made by postal notes, money- 

 orders, or by money sent in registered letters. Drafts 

 should be made payable in Washington, New York, 

 Boston, or Philadelphia. 



Subscription-price before April ist, $1 per year, in 

 advance. All subscriptions after this month begin 

 with the January number. After April ist the sub- 

 scription-price will be ;^i.5o. 



The regular receipt of the Journal will be an ac- 

 knowledgment of payment. 



The Journal Next Year. — As 

 there has been one leading feature in 

 the Journal this year, in the articles 

 on Microscopical Technic, so next 

 year it is proposed to publish a series 

 of illustrated articles, describing in a 

 popular way some of the objects which 

 are sure to be found by microscopists 

 in the course of their work. The 

 subjects have not yet been selected, 

 but the plan has been thought out, and 



will be more definitely announced 

 either in December or January. 



We are obliged to admit that some 

 aiticles which were mentioned as 

 likely to appear in the current volume, 

 properly belonging in the series first 

 mentioned above, have not yet been 

 published. The series v^^ill, there- 

 fore, be continued next year. It is 

 not possible to estimate just how 

 much space a series of unwritten ar- 

 ticles will occupy. The subjects re- 

 maining to be treated relate to the 

 methods of observation v\^ith the mi- 

 croscope, and involve a description of 

 some accessories, with instructions 

 for using them. 



Our readers may feel assured that 

 next year the Journal will be full of 

 such interesting matter as will enable 

 it to maintain its position as the lead- 

 ing microscopical journal in the coun- 

 try, and, we may repeat, the only one 

 devoted solely to the encouragement 

 and advancement of scientific study 

 with the microscope, and published 

 independently of any considerations 

 of personal gain or business interest. 



New Method of Staining. — The 

 inethod of staining described by Dr. 

 Councilman in this number gives re- 

 sults which, for the purposes men- 

 tioned, leave nothing to be desired. 

 We would call the special attention of 

 pathologists to this method as one par- 

 ticularly useful in tracing the course of 

 degeneration in nei"ves. The method 

 is a nev^ one, scarcely known in this 

 country as yet, although it has been 

 emploj'ed by Dr. Councilman in the 

 laboratory of Johns Hopkins Univer- 

 sity, where, a short time ago, v^e had 

 the pleasure of examining some of the 

 excellent pi'eparations made in the 

 manner described. 



Some General Remarks. — The 

 fifth volume of this Journal is draw- 

 ing near the end, and it is with no 

 little satisfiiction that we can look 

 back over the five years of its exist- 

 ence and see here and there signs of 



