ELECTRIC SLIDE WARMER 
FOR MOUNTING PARAFFINE SECTIONS 
Cover for Slide Warmer 
21070. Slide Warmer 
Slide Warmer for Mounting Paraffine Sections, designed by Prof. S. Walter Ranson, of 
the Northwestern University Medical School, as a convenient method for the heating of slides 
in the mounting of paraffine sections slowly and evenly over their entire extent to a tempera- 
ture just below the melting point of paraffine, giving a maximum flattening without damage 
to the section. 
The apparatus consists of an electrically heated block of transite 24 inches long by 6 
inches wide by J inch thick on a brass frame 3 inches high and fitted with an electric thermostat 
so that the temperature can be held constant at any desired temperature. The heating is accom- 
plished by a series of ni chrome wires embedded in the block of transite, and the apparatus may 
be attached to an ordinary lamp socket. The surface upon which the slides may be placed 
measures 24 x 6 inches and will accommodate 40 slides at once. It is only necessary to place 
the sections in position on the albumen-water covered slides and set the slides on the appara- 
tus. The temperature is gradually raised and the paraffine spreads without melting. 
With paraffine of 55° Prof. Ranson has obtained the best results when the regulator was 
set so that the thermometer in the apparatus registered 43°. The thermometer is placed just 
below the block of transite and registers a temperature somewhat less than that on the upper 
surface of the block. It is not necessary or desirable to remove the water from the slides after 
the sections are flattened as it evaporates in a few minutes. The time required for drying can 
be cut down from 24 hours at room temperature to 2 or 3 hours at a temperature just below 
the melting point of paraffine. A light, ventilated metal cover is placed over the apparatus 
while the sfides are drying, to protect them from dust. The apparatus requires no further 
attention until the slides are sufficiently dry to go into xylol. 
No. 21070 Electric Slide Warmer, complete with metal cover, $33.00 net 
ARTHUR H. THOMAS COMPANY 
IMPORTERS- DEALERS — EXPORTERS 
LABORATORY APPARATUS AND REAGENTS 
WEST WASHINGTON SQUARE PHILADELPHIA, U. S. A. 
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