159 



The American Medical Library and Intelligencer. By Robley 

 Dunglison, M. D. Nos. 15, 16, 17 and 18. — From the Editor. 



The Committees of Finance and Publication, respectively 

 made their Annual Reports, which were, on motion, accepted. 



Doctor Hare made the following verbal communication 

 relative to the application of radiant heat to glass. 



Dr. Hax'e said, it did not appear to him that sufficient attention had 

 been paid by artists or men of science, to the great difference which 

 existed between the effect upon glass of heating it by radiation and 

 by conduction. When exposed to radiant heat alone, unaccompanied 

 by flame, or a current of hot air, glass is readily penetrated by it, and 

 is heated, within and without, with commensurate rapidity; but, in 

 the case of its exposure to an incandescent vapour or gas, the caloric 

 could only penetrate by the process of conduction ; and, consequently, 

 from the inferior conducting power of glass, the temperature of the 

 outer and inner portions of the mass would be so different, as by the 

 consequent inequality of expansion to cause the fracture, which was 

 well known, under such circumstances, to ensue. 



The combustion of anthracite coal, in an open grate, in his labora- 

 tory, having four flues of about 4.12 by 2.12 inches each, in area, 

 just above the level of the grate, (the upper stratum of the fire, having 

 nothing between it and the ceiling,) had allowed him to perform some 

 operations with success, which formerly he would have considered 

 impracticable. The fire having attained to that state of incandes- 

 cence to which it easily arrives when well managed, he had, on open- 

 ing a hole by means of an iron rod, so as to have a perpendicular 

 perforation extending to the bottom of the fire, repeatedly fused the 

 beaks of retorts of any capacity, not being more than three gallons, 

 causing them to draw out, by the force of gravity, into a tapering 

 tube; so that, on lifting the beak from the fire, and holding the body 

 of the retort upright, the fused portion would hang down so as to form 

 an angle with the rest of the beak, or to have any desired obliquity. 

 By these means, in a series of retorts, the beak of the first might be 

 made to descend through the tubulure of a second; the beak of the se- 

 cond through that of a third, and so on ; the beak of the last retort 

 in the row being made, when requisite, to enter a tube passing through 

 ice and water in an inverted bell-glass. 



By means of the anthracite fire, as above described, thick rods, as 



