Chap. XVI. Ai>pendix, No. 2.

305

1 Contra, Ck.

By 10 cwt. of coke, being part of the residuum of15 cvvt. coals enclosed in the retorts, or 2-3ds ofthe weight, say only at 8d. per cwt. - - L. 0 6 8

By75hb. coal tar, additional residua, or 5 per cent,of the weight of the coals—say only - - 0 6 0

Net cost -.124

N. B, This is about 10 lights per hour for 1 far-thing, or one fortieth of a penny for each

light. —-'

I ..1 15 0

Now, 1000 candles, burning ten hours each, or, what is thesame thing, 10,000 candles one hour each, will consume 250 lib.,which, at only Is. per lib. will amount to 12/. 10s. Hence thedifference in favour of gas light to that of candles, in the coalcounties of Scotland , is about eleven to one.

But this disparity, even great as it is, is not so much when thework is small, and the number of lights not numerous; Besides,the attention it requires and excites, counterbalances a good dealof the savings. Accidents sometimes also happen from inatten-tion ; as, when a large quantity of the gas gets mixed with at-mospheric air, and the compound inflamed, the explosion is verydangerous.

A few years ago, several shops—first, in Glasgow , then inEdinburgh , and other towns—-were lighted up with this gas ; butit required so much management and work,—produced so muchheat and smell, when the tubes leaked, and all not in proper or-der,—that few have persevered in using it. Indeed, it is onlyon a large scale that it, as yet, can be employed with advantage.

Scotland lying mostly between the 55th and 60th degrees of■northern latitude, her days, in winter, are necessarily very short;the shortest being little more than from nine a. m. till three p. m. ;ond, particularly in that season, often rendered, by meteorolo-g'oal causes, very obscure. Hence, the annual consumpt of oilone! tallow for producing light is very great. If each individualrequires half an ounce of either of these, or one hour’s lightdaily, on an average, the weight for one year is 9165 ton*; whichalso averaging, at 55/. per ton, exceeds half a million Sterling.So that, whatever savings can be introduced into this department^must necessarily diminish, besides oil, the quantity of tallowpurchased from foreign powers.

2. Lime. —The advantages of lime, which Scotland possesses,are very great. From the abundance of calcareous stone, as"’ell as coal, it is obtained very cheap. Without this, it couldpot be so beneficially applied to most of the purposes for which11 m so conspicuously formed : such as, building and manuring ;a flux in iron making ; also in sugar refining, bleaching, and

U 2