A CONVENIENT PARAFFINE BATH FOR 

 INDIVIDUAL USE. 



J. F. McCLENDON. 



Paraffine baths may be classified according to source of heat, 

 into oil, gas and electric ; and according to mode of regulation 

 of temperature into fixed, regulated by attendant and self-regu- 

 lating. In the self-regulating baths, the amount of heat generated 

 may be variable or the loss of heat variable. In using oil and 

 gas there is more danger from fire than in using electricity. 

 Baths with a fixed temperature regulation can be used only in 

 rooms of approximately constant temperature, and their readjust- 

 ment by an attendant is inconvenient. Apparatus for controlling 

 the amount of heat generated is too delicate and expensive to be 

 put in the hands of all students. There only remains the elec- 

 tric bath, self- regulated by varying radiation of heat. Several 

 forms of baths using this method have been used, and the form 

 herein described differs from them chiefly in size, shape and 

 material. 



The bath consists of a rectangular concrete trough having in- 

 side measurements of 21.5 cm. in length, il cm. in width and 

 9.5 cm. in depth, and a general thickness of about 3.5 to 4 cm. 

 In making these troughs I molded the inside with some old pieces 

 of glass and left the glass in as a lining (in case this was not done 

 the inside might be painted or left bare — the paraffine would not 

 soak through so long as the outside is below its melting point). 

 The trough is filled with paraffine of melting point one degree or 

 more (3 in present instance) higher than that used in imbedding. 

 The top is closed by a thin piece of wood in the center of which 

 is a flush lamp socket with opening downward. Into this socket is 

 screwed a four candle power" incandescent " lamp of the spheri- 

 cal type. The lamp reaches about to the bottom of the trough, 

 while the socket projects upward above the top of the bath and 

 is connected by small flexible wires or lamp cord to a no-volt 

 circuit. In the wooden top near the lamp are cut holes of suit- 



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