46 Mr. Ricardo's Reply to Mr. Low [July, 



ments of oil and coal gas for 1000 lights, one consuming 2,000,000, 

 the other 7,000,000 cube feet. I merely stated the number 

 of lights hypothetically, applying equally to both establishments. 

 It was a matter of no importance whether I stated 1000 or 

 10,000 lights, my deductions were from the quantity of gas pro- 

 duced and consumed. Had I stated 1200, or 1300 lights, in- 

 stead of 1000, Mr. Low would have lost the opportunity of ex- 

 pressing so much astonishment, although the argument would 

 have remained precisely the same ; and 1 believe it will be found 

 that, in estimating the quantity consumed during the longest 

 night, I have rather under than over-rated it. 



The number of retorts required for an establishment consum- 

 ing 7-000-000 cube feet of coal gas annually, I have taken from 

 Peckston's work, the best authority extant. I have made al- 

 lowances for wear and tear, and repairs ; but I have done that 

 as largely in the number which I have estimated for the oil ^as. 

 As for the improvements which Mr. Low mentions, I have heard 

 of many that have been proposed, but of none that have been 

 successfully put in execution. I believe a great many have been 

 tried, but have most generally been abandoned. 



Mr. Low has stated, somewhat triumphantly, what has been 

 done, or rather what is doing, at Derby, to prove the decided 

 superiority of coal over oil gas. Gas is there to be furnished at 

 the expense of the contractor for Is, Sd. per 1000 cubic feet, and 

 delivered into the company's gasometer; for which they are to 

 charge 7s. 6d. to the consumer, and they expect to derive a 

 profit of 10 per cent. Without thinking it necessary to remark 

 upon the disproportion between the cost and selling price, 1 will 

 just examine the correctness of the above statement. I have 

 been furnished with a printed rate table of the half-yearly prices 

 of the Derby gas light burners, and a most curious table it is. 

 Retailing gas, from the light of a farthing candle up to a large 

 argand burner, — the method by which the quantity of gas that 

 passes through one of these burners is regulated, so that each con- 

 sumer may have precisely his quantity and no more, — the mode on 

 which their cocks are so constructed, that the full turn shall be 

 the maximum, — and the exactness with which the pressure of 

 the gasometer shall at all times, and under all circumstances, be 

 equalised, are, I suppose, among some of those late improve- 

 ments that have been alluded to. That the company mean to 

 keep strictly to the letter of the contract on the part of the con- 

 sumer, is evident from the threats they hold out of penalties, fines, 

 and taking before magistrates ; all of which must be a great re- 

 commendation to induce persons to become consumers. We will 

 now examine the correctness of Mr. Low's statement, that gas 

 is sold at 7s. 6(7. per 1000 cubic feet. If a person contracts for 

 a burner consuming five cubic feet per hour, till 10 o'clock, the 

 average time of lighting will be 3 -t- hours per night, according 



