82 Dr. Andrew Fyfe on the Comparative Value of 



former 9500, then the value of the coals for the amount of light 



afforded by the combustion of their gases, is as 61 to 1. 



The above must be considered as the value of the Scottish 

 parrot coals on an average, or as used in their mixed state, as is 

 generally done by gas companies. It may be interesting to state 

 the value of some of the coals themselves. The poorest Scot- 

 tish parrot I have yet examined yielded only 9000 feet of gas, 

 the value of which was 2 2 to that of English caking-coal gas 

 as 1 ; making, accordingly, the value of the coal for yielding light 

 only 2 5, or very nearly so. 



The value of the gas from Lesmahago coal, which by gas- 

 makers is generally considered the best in the market, I have 

 found to be 6*6 to the English caking-coal gas as 1; the quan- 



tity of gas being 1-13 to 1; accordingly the value of Lesma- 



hago coal is at least 7 to 1. Since the publication of my paper 

 in 1842, I have had more valuable coals submitted to trial ; but 

 as these are not, so far as I know, in the market at present, they 

 must not be taken into account in fixing the average value of 

 Scottish parrot coal. As above stated, we must still consider the 

 value of this coal as about 6, to the Newcastle caking as 1 ; of 

 course its value compared with the English cannel, will be 2 6 to 1. 

 I have said that the value of the coke has not been taken into 

 account in these calculations ; it must, however, be borne in 

 mind, that, while I have fixed the value of the Newcastle coal 

 for atfording light by the combustion of its gas, as very low, 

 compared to that of the cannel coals, yet, taking into account 

 the greater quantity of coke which it yields, and the higher price 

 at which that coke is sold, the value of the coal to gas-manufac- 

 turers becomes comparatively greater than I have stated, of course, 

 10 this point of view, reducing the value of the others as com- 

 pared with it : but then this has nothing to do with the question 

 under consideration, viz., the comparative value of the coals for 



affording light by the combustion of their gases. 



3. Expense for Light by different Gases. 



Having fixed the value of the gases obtained from the vane- 

 ties of coal mentioned, I have now to advert to the prices paid 

 for the gases at different places, with the view of shewing the 

 comparative expense to consumers for the same amount of light. 



In examining this part of the subject, a difficulty occurs, owing 

 to the different methods followed in charging for gas in different 

 towns. The following remarks must therefore be considered 

 only as an approximation to the truth. 



English Caking* Coat Gas. — The charge for this gas is about 

 4s. 6d. per 1000 feet, as at Newcastle, subject to discount, by 

 which, and by charge for street-lamps, the average price may be 

 taken as 3s. lOd. Let us take this as unity. 



