386 Notices respecting Neiv Books. 



striicted as to admit of air being supplied and thrown into it with- 

 out any communication between the burner and the external air : 

 this apparatus is not larger than the steel-mill, but it is more ex- 

 pensive than the other, costing from twenty -two to twenty-four 

 shillings. 



" These lamps are all extinguished when the air becomes so pol- 

 luted with fire-damp as to be explosive. 



" 'i'here is a fourth lamp, by means of which any blowers may be 

 examined in air in which respiration cannot be carried on : that is, 

 the C/iarcoal. lamp. This consists of a small iron cage on a stand, 

 containing small pieces of vert/ ivcll burnt charcoal blown up to a 

 red heat. This light will not inflame any mixtures of air with fire- 

 damp *. 



" Of these inventions, the Safe lamp, which is the simplest, is 

 likewise the one which affords the most perfect security, and re- 

 quires no more care or attention than the common candle, and 

 when the air in mines becomes improper for respiration, it is ex- 

 tinguished, and the workmen ought immediately to leave the place 

 till a proper quantity of atmospheric air can be supplied by venti- 

 lation. 



" I have made many experiments on these lamps with the ge- 

 nuine fire-damp taken from a blower in the Hepburn Colliery, col- 

 lected under the inspection of Mr. Dunn, and sent to me by the 

 Rev. Mr. Hodgson. My results have been always unequivocal. 



" I shall immediately send models of the different lamps to such 

 of the mines as are exposed to danger from explosion ; and it will 

 be the highest gratification to me to have assisted by my efforts a 

 cause so interesting to humanity." 



The Safety lamp as now perfected, and the principle upon which 

 the safety depends, are so well known as to require no further elu- 

 cidation. We fully agree with Dr. Paris, that " it was the fruit of 

 elaborate experiment and close induction ; chance, or accident, 

 which comes in for so large a share of the credit of human inven- 

 tion, has no claims to prefer upon this occasion; step by step may he 

 be followed throughout the whole progress of his research, and so 

 obviously does the discovery of each new fact spring from those 

 that preceded it, that we never for a moment lose sight of our phi- 

 losopher, but keep pace with him during the whole of his curious 

 inquiry." 



[To be continued.] 



• " Tn addition to these four lamps, we learn from an Appendix to his 

 paper in the Philosophical Transactions, that in the beginning of his in- 

 quiries, he constructed a close lantern, which he called the Fire-valve 

 lantern; in which the candle or lamp burnt with its full quantity of air, 

 admitted from an aperture below, till the air began to be mixed with fire- 

 damp, when, as the fire-damp increased the flame, a thermometrical spring 

 at the top of the lantern, made of brass and steel, riveted together, and in a 

 curved form, expanded, moved a valve in the chimney, diminished the cir- 

 culation of air, and extinguished the flame. He did not, however, pursue 

 this invention, after he had discovered the properties of the fire-damp, on 

 which his Safety-lamp is founded." 



XLIX. Pro- 



