352 THE AMERICAN MONTHLY [Dec, 



One is the division of Microscopes and accessories, Microtomes 

 and accessories, and apparatus for Photo-Micrograi:)liy, and 

 Bacteriological and Laboratory supplies, each article being dis- 

 tinctively enumerated under their respective headings. There 

 is embodied in this edition as complete a line of apparatus as 

 is needed for general Microscopical work, both for the individ- 

 ual as well as for laboratory purposes, so that the catalogue is a 

 handy reference book for the intending purchaser. 



We note the fact that the sj^iral rack and pinion is used only 

 for the coarse adjustment, and that they are cut with specially 

 devised automatic machinery. 



Among new instruments we notice the W Laboratory Dis- 

 secting microscope which is designed for use in laboratories. 

 There are some changes in the construction of Microtomes; the 

 object holder with its various adjustments is made considerably 

 heavier; its vertical adjustment on the slide is made to act with- 

 out disturbing the relation of the specimen to the knife and the 

 inclination of the object in either direction by universal joint ; 

 the method of feeding the screw has been changed to remove 

 the possibility of making failures ; permanent lever which is 

 provided with a reversible pawl acts in either direction on the 

 milled edge of the disk and works within a definite limit which 

 is prescribed by two set screws attached to the arc of a fixed 

 circle. 



The list of Bacteriological apparatus, Water-baths and ovens, 

 has been considerably increased. In the line of glass-ware, they 

 have increased their stock of such articles as are most needed 

 for Bacteriological Laboratories. A pocket set of dissecting in- 

 struments in leather case is considered very unique and will 

 meet with a great deal of favor on account of its neatness and 

 practicability. 



There will be found a number of testimonials from well-known 

 scientists who have used the Continental and American type of 

 microscopes and objectives. 



Another new feature is an article on Microtome knives and 

 their care, which we consider very important, as it gives con- 

 siderable information on the subject, valuable to the user of 

 microtome knives. The}' also include aside from the microtome 

 knives a series of section razors, hones and strops. 



