APPENDIX I 173 



as an assembly room for a division at the beginning and close of 

 school, drawers and shelves beneath the desk are of little real use, 

 and often become mere receptacles for laboratory debris, unless 

 they are provided with locks. It is usually far safer and more satis- 

 factory to collect drawings, magnifiers, pencils, etc., at the close 

 of the period, and to distribute materials as they are needed during 

 the next period. If this work is properly systematized and the 

 assistance of pupils is made use of, very httle of the laboratory 

 time is lost in this way. 



Seats fixed to the floor, likewise, are of great advantage. The 

 authors have found that the best seat for this purpose is the Chandler 

 chair, which is furnished by the American Seating Company, 

 19 West 18th St., New York City. It has a strong iron base, which 

 can be screwed to the floor, and the chair seat turns on ball-bear- 

 ings through an arc of 180 degrees. The price of the chair is $2. 



Apparatus and chemicals. — The following lists of apparatus 

 and chemicals are suggested as a minimum equipment for a class 

 of 24. Most of the items can be purchased from any one of the fol- 

 lowing dealers : 



Bausch and Lomb Optical Co., Rochester, New York. 

 Kny-Scheerer Co., 404 West 27th St., New York City. 

 0. T. Louis, 59 Fifth Avenue, Nej\r York City. 



Quantity Apparatus and Glasswabb Estimated Price 



1 Compound microscope, with |- and ^inch objec- 

 tives, double nose-piece, 1 inch eye-piece, and 



revolving disk-diaphragm $30.00 



24 Magnifiers, doublets, IJ-inch focus ... . 16.20 



1 Harvard trip-scale balance ... .... 6.00 



12 Evaporating dishes, 3 inches diameter ... . 1.50 



1 2-quart agate double boiler 1.50 , 



2 Alcohol lamps or -50 



2 Bunsen burners (if gas is available) .40 



3 ft. Rubber tubing (heavy) to fit Bunsen burners . . .60 

 144 Slides, plain, 1X3 inches 80 



