214 The Microscope. 



removing the paraffin. Transfer it back to the alcohol for five min- 

 utes to clean out the xylol, and then wash gently in distilled water. 

 With ammonia-carmine fill a salt-cellar about one-quarter full and 

 immerse the carefully -flattened specimen in it. About five minutes 

 is consumed in the staining, after which the specimen is again washed 

 in distilled water to which a few drops of acetic acid have been add- 

 ed. The acid acts as a mordant, fixing the dye in the nuclei. Now 

 transfer to the strongest alcohol to remove the water, then to turpen- 

 tine or clove- oil, and finally to Canada-balsam, as described in the 

 previous lesson. 



MICROTOMES. 



A few words on this subject may not be amiss here. A very 

 simple microtome, used to some extent by the writer, is the " New 

 Model," manufactured by Jas. W. Queen & Co., of Philadelphia. A 

 description of this instrument will be found in the January number 

 of this Journal. One made by Schanze, of Leipzig, has proved ex- 

 tremely useful, specimens being cut with great rapidity and exact- 

 ness. Specimens do not generally require imbedding when used on 

 this instrument. Bausch & Lomb, of Rochester, N. Y., and W. H. 

 Bullock, of Chicago, make a microtome after the Schanze model, to 

 which they have added some improvements. W. H. Walmsley & Co., 

 Philadelphia, make a modification of Rivet's microtome. The speci- 

 men is fed to the knife by means of an inclined plane, as in the 

 Thoma instrument, thus securing great accuracy. The Thoma 

 microtome, which is one of the best in the market, is manufactured 

 in this country by the Educational Supply Company, of Boston, 

 Attention is also called to the new Ryder microtome, described in 

 our last number, which bids fair to become one of the most useful 

 of this class of instruments. The prices of these various instru- 

 ments ranffe from $12.00 to $50.00. 



EDITORIAL. 



SOME RECENT ADVANCES IN BACTERIOLOGY. 



So great is the interest in this fundamental branch of medicine, 

 and so large has become its current literatui'e that a weekly journal 

 devoted exclusively to bacteriology is necessary to satisfy its devotees 

 and record their researches. 



The journal will be known as the CentralbJatt fiir Bacteriologie 

 und Parazitenkunde. It is published in Jena, and edited by Dn 



