March 13, 1896.] 



SCIENCE. 



381 



It is in every way preferable to separate 

 the generator and the gas holder, and such 

 arrangements can easily be made automatic. 



The acetylene company has patented a 

 tank for generating the gas under sufficient 

 pressure to liquify itself, and proposes to 

 distribute liquid acetylene in cylinders under 

 a pressure of 600 to 700 pounds to the inch; 

 of this project more is to be said later. 



It is certain that a company purchasing 

 the carbide of calcium and using an exist- 

 ing gas plant could generate acetylene and 

 distribute it through mains at a very small 

 expense, and with little skilled labor, so 

 that when a price for the carbide had been 

 established by contract the cost of the gas 

 could be easily estimated ; let us see what 

 price such a company could expect to ob- 

 tain from a consumer. 



VALUE OF ACETYLENE AS AN ILLUMINANT. 



Suppose we take the case of a competition 

 with the gas companies of a large town. At 

 first sight it would seem fair to say we pay 

 for the light gas gives, and if a new gas 

 gives ten times more light we are willing to 

 pay ten times more, particularly if it 

 possesses any other advantages; our gas 

 bill will remain the same. 



Here we come upon ground where the 

 facts can be tested by experiments. I 

 have made a large number of measures of 

 illuminating power and find that with a 

 new burner particularly suited to it 5 cu. ft. 

 of acetylene per hour will give 200 candle 

 power ; 5 cu. ft. of Boston gas will give a 

 little more than 25 candle power. The 

 Brookline gas is a little brighter. From 

 this point of view alone then we can pay in 

 Boston about $8 per 1,000 cu. ft. for acety- 

 lene when we pay $1 per 1,000 cu. ft. com- 

 mon gas. But will the gas bills remain the 

 same at this ratio ? More light will probably 

 be used and the householder will be led into 

 a more extravagant consumption, and he 

 must decide what he is willing to pay for 



the new luxurJ^ We must count then with 

 the tastes of the consumer, and these can 

 only be translated into money values after 

 long trial of the new light in many houses. 



, Besides the question of meeting the desire 

 of the consumer for more or less light is 

 another, which must be taken into consider- 

 ation depending upon his expertness in 

 burning gas and the care he is willing to 

 take in getting economical results. 



No. 1. A Sugg- table fishtail burner is 

 shown, burning just 5 cu. ft. per hour and 

 giving the light of 25 candles. If more or 

 less than 5 cu. ft. of gas is passed through 

 it per hour it gives a lower efficiency and 

 the light costs more. The law in Massachu- 

 setts, 1882, requires that the candle power 

 should be tested with the most efficient 

 burners, and I have used the best one 

 for water gas. Coal gas would have given 

 more candle power in an Argand burner. 

 Burning gas economically is an art which 

 is only understood by experts, and here 

 again the habits of consumers disturb 

 calculations; they are not usually willing 

 to take the pains to get the best burners, as 

 the following experiment will show. 



ISTo. 2 is a gas burner taken off the pipes 

 in the Technology building and represents 

 the average condition of burners in dwell- 

 ings. About one-half the illuminating 

 power of the gas is lost in this burner, 

 and few people think of having the burners 

 changed when they become inefficient. 



If I put a globe over the burner, about 

 half the light is absorbed, so that with a 

 bad burner and with a milk-glass globe we 

 pay about four times as much as need be 

 for light ; but the use of a globe is often 

 necessary for comfort. The acetylene gas 

 gives a different colored light, and I thought 

 it might pass through the globe in larger 

 proportion, but on measuring the candle 

 power I found this was not the case. Per- 

 haps a globe can be found that will espe- 

 cially suit acetylene light. 



