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lupton: safety lamps. 
by a ring, the ring may be unscrewed by turning the glass, and thus 
the lamp may inadvertently be made unsafe. 
Wolf Lamp. This can be re-lighted without opening. This 
relieves the collier from the temptation to open his lamp to re-light 
it, but it is a question, whether, if re-lighted in an explosive mixture, 
the flame might pass the gauze and cause an accident. 
The Morgan Lamp (see figs. 9 and 10) is a safe lamp if the glass is 
locked and it gives a good light, like all lamps with the Mueseler 
chimney it is easily put out accidentally which is annoying. It has 
successfully resisted all trials up to 3200 feet per minute, but it can 
be exploded with very high velocities. 
The Evan Evans Lamp (see fig. 11), is so made that it extin- 
guishes itself when hot ; the heat melts a soldered joint and then a 
spring is liberated which causes a cap to descend and close the air- 
holes. 
The Protector Lamp (see fig. 6) cannot be opened without 
putting out the light, and the spirit they burn gives a good 
light with no trouble because the wick does not char ; in using the 
spirit precautions must be taken and a specially arranged lamp-room 
made, because, if carelessly used it is sure to set fire to the lamp- 
room ; as far as the lamp itself is concerned, when once it is locked 
the spirit is as safe to use as Colza oil and much cleaner. 
The Clifford Lamp (see fig. 12) has several ingenious novelties. 
The double bonnet is so designed as to equalise the pressure of the air 
current on a lamp at the inlet and outlet so as to prevent it taking 
effect upon the light, in fact to make a perfect shield. In place of 
wire gauze there is a perforated plate made up of a copper and lead 
plate superposed so that if the lamp gets hot the lead will melt, the 
intention is to close up the air holes in the copper and put out the 
flame. The lower end of the chimney terminates in a bell of glass 
covering the flame ; this diminishes the light, but by the means of 
this bell the lamp can be tilted without being upset. Mr. Clifford 
claims that his lamp will resist any velocity and that it has resisted 
a speed of 12000 feet or over two miles a minute. I saw it tested 
at a pressure of 1'4 inch of W. G. and it got red-hot but extinguished 
