50 



TRANSACTIONS OF THE AMERICAN INSTITUTE. 



Giuseppe Tagliabue's Patent Coal-Oil Pyrometer, 



For which the Silver Medal of the American Institute was awarded. 



This cut represents two views of 

 the Coal -Oil Pyrometer. The first 

 one is as it appears when it is ready 

 to test the burning point of the oil, 

 with the sliding cover turned one 

 side ; and the second view is when 

 it is ready to test the explosive 

 point of the vapor of the oil. The 

 lower part of the instrument con- 

 tains a bath of water, with a lamp 

 beneath, for the purpose of heat- 

 ing the water. Within the water 

 bath is a cup for containing the 

 oil which is to be tested. Over 

 this water bath and oil cup is a. 

 cover with a thermometer through 

 it, and reaching down into the oil 

 in the cup. The short cylinder on 

 the sliding cover is for collecting 

 the vapor of the oil when testing its inflammability. When the oil 

 to be tested is placed in the oil cup, the lamp is lighted (burning 

 with a small flame) and placed under the water bath, and the water 

 and oil is gradually heated. The oil emits a vapor in proportion 

 to its volatility. This vapor mingles with the atmospheric air, 

 which is admitted through two perforations (marked d in the 

 sliding cover), and thus forms an explosive mixture that ascends 

 into the cylinder on the sliding cover; and on applying a lighted 

 taper a slight explosion or puff of flame will take place, and on 

 simultaneously inspecting the thermometer the temperature of its 

 inflammability will be ascertained. After turning the sliding cover 

 one side, as in the first view, and holding the lighted taper in con- 

 tact with the escaping vapor till the oil ignites, on looking at the 

 thermometer the burning point will be noted. 



DIRECTIONS FOR USE. 



1. Lift off the cover, take out the oil vessel, and fill the water 

 bath with water until the surface is just a quarter of an inch above 

 the hent ends of the wires, or the support for the oil cup. 



2. Fill the oil vessel with oil until it rises to within a quarter of 

 an inch from the top of the vessel, or level with the top of the ring 

 for the thermometer ; then replace the oil cup within the bath, 

 observing to press the projection on it into the groove or notch. 



