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XLIX. Description of a new Spirit-lamp Furnace. By 

 ARTrfUR Trevelyan, EsqJ* 



TTAVING lately been engaged in following out chemical 

 -■--■■ analysis under the able direction of William Gregory, 

 M.D., Edinburgh, I found that a lamp for generating a great 

 heat would be highly useful, and was much wanted by the 

 analytical chemist. After experimenting to a great extent with 

 many modifications of the lamps of 13erzelius and others, I 

 found that they all wanted power, and when used for a length 

 of time, attained such a temperature that the spirit boiled 

 and flowed over. After continuing these experiments for nearly 

 three months, I had almost relinquished them in despair of 

 success, when I accidentally became acquainted with Andrew 

 Whelpdale, a young and promising chemist, to whom I stated 

 my difficulty : he recommended, if it could be contrived, that 

 the vapour of alcohol should be used. I immediately came 

 into his view, and had a lamp constructed, of which a drawing 

 is inclosed (see the figure). After trying it with different 

 burners, a stop-cock and safety-valve (neither of which is 

 necessary) and differently formed chimneys, it was brought 

 to a state of perfection and power 

 "which we little expected. It fused 

 liquid as water, 500 grains of 

 bicarbonate of soda in fifteen mi- 

 nutes, consuming three ounces of 

 alcohol, and I think might do it 

 in less time, but the chimney was 

 rather small for the size of the 

 platina crucible used : the ends 

 of the brass uprights attached to 

 the rim on which the chimney 

 stands were fused in a similar 

 experiment. 



From its great power I think 

 it may be called emphatically 

 the " Lamp-furnace." 



It may be made of any size, 

 but the chimney must be suited 

 to the crucible, round which the 

 flame should play freely. 



The vapour may be generated 

 by a spirit-lamp placed under- 

 neath the globe. 



* Communicated hv the Author. 



