and Laboratory Methods. 



1911 



over the rubber, in that it does not rot, does not permit escape of gas, and is safe 

 in case the flame strikes back. 



The desks are arranged in three rows facing the east side of the laboratory, 

 which is lighted by eight large windows, reaching to the ceiling and occupying 

 almost the entire side of the laboratory. These furnish a most admirable light 

 for microscopical work. If the light is too intense during morning sessions, it 

 may be softened by drawing the white shades with which the windows are pro- 

 vided. On dark days or afternoons during the winter months the incandescent 

 light (16 c. p.), which is suspended over every desk, may be used. It is desir- 



FiG. 2. — Individual Students' Desks and Lockers. 



able in connection with these to use a screen having a metal base, formed of a 

 small tin dish filled with lead, in which a wire is inserted bent at right angles at 

 the top. Upon the horizontal arm of the wire is hung a sheet of common 

 manila paper of such length that the lower part of it will be just above the stage 

 of the microscope. As the student sits facing the light, the eye-shade is placed 

 between the source of light and the microscope, excluding the light both from 

 the eyes and from the upper surface of the object. By the use of this screen no 

 ill effects on the eyes result from artificial illumination. By skillful manipulation 

 of mirror and condenser excellent results may be attained in the way of lighting 

 the field. 



The heat and odor common to a bacteriological laboratory make the matter 



