Oitf THE SOCIAL BENEFITS OF PARAFFIXE. 117 



astonished to find respectable people, and even unprotected 

 females, going alone, unarmed and without fear, at night, up 

 the by-streets which in his days were deemed so dangerous, 

 and he would soon perceive that the bright gaslights had done 

 more than all the laws, the magistrates, and the police, to drive 

 out those crimes which can only flourish in darkness. The 

 intimate connection between physical light and moral and intel- 

 lectual light and progress is a subject well worthy of an exhaus- 

 tive treatise. 



We must, however, drop the general subject and come down 

 to our particular paraffine lamp. In the first place, this is the 

 cheapest light that has ever been invented cheaper than any 

 kind of oil lamp cheaper than the cheapest and nastiest of 

 candles, and, for domestic purposes, cheaper than gas. For 

 large warehouses, shops, streets, public buildings, etc. it is 

 not so cheap as gas should be, but is considerably cheaper than 

 gas actually is at the price extorted by the despotism of com- 

 mercial monopoly. 



The reason why it is especially cheaper for domestic pur- 

 poses is, first, because the small consumer of gas pays a higher 

 price than the large consumer ; and secondly, because a lamp 

 can be placed on a table or wherever else its light is required, 

 and therefore a small lamp flame will do the work of a much 

 larger gas flame. We must remember that the intensity of 

 light varies inversely with the square of the distance from the 

 source of light ; thus the amount of light received by this page 

 from a flame at one foot distance is four times as great as if it 

 were two feet distant, nine times as great as at three feet, six- 

 teen times as great as at four feet, one hundred times as great 

 as at ten feet, and so on. Hence the necessity of two or three 

 great flames in a gas chandelier suspended from the ceiling of a 

 moderate-sized room. 



In a sitting-room lighted thus with gas, we are obliged, in order 

 to read comfortably by the distant source of light, to burn so 

 much gas that the atmosphere of the room is seriously polluted 

 by the products of this extravagant combustion. A lamp at a 

 moderate distance say eighteen inches or two feet, or there- 

 abouts will enable us to read or work with one tenth to one- 

 twentieth the amount of combustion, and therefore with so 

 much less vitiation of the atmosphere, and, if we use a paraffine 

 lamp, at much less expense. 



But the chief value of the paraffine lamp is felt where gas is 

 not obtainable in the country mansion or villa, the farm- 



