218 



THE AMERICAN MONTHLY 



[November, 



Zinc White Cement Again. — 

 A correspondent relates some facts 

 concerning the use of zinc white ce- 

 ment, in another column, which are 

 strongly confirmatory of the opinions 

 that have been several times expressed 

 by ourselves. The same testimony 

 has been given by many others ; and 

 in some cases when persons have 

 called in question the accuracy of our 

 previous assertions concerning this 

 matter, we have been able to convince 

 them that we were in the right by 

 looking through slides in their own 

 cabinets. We have not at any time 

 stated that zinc white cement never 

 proves satisfactory, for it would be 

 strange indeed if some mounts made 

 with it should not remain perfect. 

 What we have said, and still main- 

 tain as the result of practical expe- 

 rience, is that zinc white cement can- 

 not be dejDended upon. It may do 

 as a finish, but not for the practical 

 purposes of a cement. 



We refer to the subject at length 

 because of its importance to every 

 mounter, but we are especially led to 

 bring it prominently forward again 

 because a certain writer in St. Louis 

 has recently recommended its use. 

 Now, it is impossible for us to believe 

 that the author in question was not 

 aware of what we had said concern- 

 ing this cement, yet he deliberately 

 tells his readers to use it, without so 

 much as a hint that it has been de- 

 clared unreliable. We do not expect 

 that every reader of this paper will 

 rely absolutely upon the opinions ex- 

 pressed in these editorial columns — 

 far less those whose experience has 

 been such as to give them undue con- 

 fidence in their own judgment and 

 wisdom. Nevertheless, even though 

 an individual has used zinc white suc- 

 cessfully for years, the experience of 

 others should have some weight ; and 

 any person who assumes to give in- 

 struction without regard to the expe- 

 rience of others, pursues a course of 

 injustice to all and discreditable to 

 himself. 



Fortunately, most of our readers 



know very well that nothing finds its 

 way into these columns that is not 

 from a good source and worthy of 

 confidence. We are endeavoring to 

 do all we can to assist microscopists, 

 and we do not like to see others try 

 to imdo it, even though they may 

 write with the best of motives — which 

 we fear is not always the case. 



NOTES. 



— We have just received a preparation 

 of the Bacillus tuberculosis, prepared 

 strictly in accordance with the method 

 given in the preceding number of the 

 Journal, which is far superior to any 

 preparation of the kind we have ever 

 seen. It was prepared by Dr. J. C. Mc- 

 Connell, of the Army Medical Museum, 

 and shows the bacilli in great abundance 

 and with remarkable sharpness. Not one 

 of the German preparations we have seen 

 is equal to it ; in fact, we did not suppose 

 it possible to get such a fine definition of 

 the organism as this mount affords. 



— We trust that readers do not neglect 

 to keep a close watch of the advertising 

 pages from month to month, as new arti- 

 cles are being constantly offered for sale, 

 and it frequently happens that the supply 

 of some of them is not large, and there- 

 fore it is soon exhausted. This month 

 Messrs. Walmsley & Co. have changed 

 their advertisement throughout. Mr. Em- 

 merich offers a very full line of Zeiss' ob- 

 jectives, just received. It will also be 

 noticed that he has made a change in his 

 business by taking his son as a partner in 

 the firm of Fr. J. Emmerich & Son. Mr. 

 J. L. Zabriskie is offering some sections of 

 wood of American trees, and Mr. Hinrichs, 

 of Baltimore, has received a new supply of 

 Marpmann's preparations. 



— We have already drawn attention to 

 the ' Harvard ' microscope stand devised 

 by the Bausch & Lomb Optical Company, 

 which was made to meet the demands of 

 those who desire stands of the continental 

 pattern. On enquiry we learn that the 

 demand for these microscopes has been 

 quite large, audit appears there is a place 

 for them, as was suggested in these col- 

 umns long ago. Those who desire in- 

 struments of the kind can now obtain 

 them from home manufacturers. We 

 have an article about microscopes await- 

 ing publication next month, which intend- 

 ing purchasers may read to advantage. 



