IV. Conclusion.—Some Practical Obser-vations.

Time of course has increased the con-fidence of the workmen in the safety lamp;and in a period of nearly two years and ahalf in the most dangerous mines in Britain,it must have been exposed to all circum-stances which the variety of explosive mix-tures can occasion. In my first trials withthe safety lamp when I found the wirebecome red hot, I thought it might beproper to cool it occasionally by water, ormoistened cloth ; but this was found un-necessary in the common practice of theminers. Whenever a single wire gauzelamp is made to burn in a very explosiveatmosphere at rest, the heat soon arrivesat its maximum, and then diminishes; andthe idea of the wires burning out, is shewnto be unfounded; the carbonaceous matterproduced from the decomposition of the oil,tends not only to prevent the oxidation ofthe metal, but likewise revives any oxidealready formed; and this coaly matter,