Scientific Lectures. 23^ 



at once extinguished. The " Mineral Sperm " is actually a fire 

 extinguisher. But this oil will stand a much more severe test. Here 

 we have a large pan of oil on a water bath. These two large alcohol 

 lamps have raised the water to boiling ; you see the steam escaping 

 from this vent; the oil is at 212° F., 112° above the standard flashing 

 point and at 102° above the standard burning point of safe oil. Yet 

 you now see that this mass of cotton waste which was saturated with 

 the oil, and was but a moment ago wrapped in flames, is now quietly 

 extinguished. The "Mineral Sperm" is a fire extinguisher even 

 when heated to 212° F. Am I wrong in saying it is • practically as 

 safe as whale oil ? 



The So-called Safety Lamps. 



A great number of safety lamps have been patented, with a 

 view to make it possible to burn the explosive, inflammable naphthas 

 without danger. Many of these have been submitted to me for 

 examination, and the conviction is unavoidable that they are anything 

 but a blessing. No matter how well they realize the idea of protect- 

 ing the oil they contain from explosion, they are treacherous friends. 

 They allay one's fears of explosive oils, and the accident, which is 

 always much more likely to occur outside than within lamps, is just 

 as likely to take place. 



The lamp is dropped and broken ; it is filled while burning ; the 

 servant neglects to screw in the wick tube ; the oil can is upset or left 

 uncorked, or the servant uses the oil to kindle the fire. In some way 

 or other fire gets to the vapor of oil, and an explosion occurs. Even 

 when the " safety lamp " has an ally in the form of a " safety can," it 

 still fails to make naphtha safe. It is an axiom that no lamp is safe 

 with dangerous oil, and every lamp is safe with safe oil. 



Half the so-called " safety lamps " are no safer than those which 

 make no claim to safety ; while the other half are only safe as long 

 as they are in perfect order, and subject to no carelessness in the fill- 

 ing or handling. Persons will be careless and thoughtless; it is 

 human nature to be so. What we want is safe oil ; with it all lamps 

 will be safe. The safety lamp is positively objectionable, as it leads 

 persons to purchase dangerous oils without question. 



Another device, by which these oils are brought into use is, by 

 means of gas lamps, so called. They are a contrivance by which the 

 volatile liquid is converted into gas, and then burned. This is sim- 

 ply the ordinary oil or naphtha placed in a lamp with a long tube run- 

 ning upward ; a wick passes up through the tube, and there is a large 



