_Enclosed are the result of a series of experiments made under my direction with a view of ascertaining the relative value of the different modes of working cast-iron cylindrical retorts, from which you will perceive that it is more economical to work eight hours charges, as the workmen call it, that is to say, to suffer the distillatory process to go on for eight hours, when nearly two bushels of coal are contained in each retort, than to discontinue the operation at the end of six hours._
_I am with respect, Sir, Yours, &c. T. S. PECKSTON._
=========+=======+================+================+========+========= Number of|Number | | |Quantity|Quantity Days the | of |Quantity of Coal| Quantity of | of | of Gas Retorts |Retorts| decomposed for | Coal used | Gas |from one were | in | obtaining Gas. | for Fuel. | pro- |Chaldron worked. |action.| | | duced. |of Coal. ---------+-------+----------------+----------------+--------+--------- | |_Chal- _Bushel._|_Chal- _Bushel._| _Cubic | _Cubic | |dron._ |dron._ | Feet._| Feet._ Monday | 87 | 10 30 | 4 24 | 94,987| 8,768 Tuesday | 88 | 14 24 | 6 8 | 128,597| 8,784 Wednesday| 88 | 14 24 | 6 8 | 122,188| 8,331 Thursday | 94 | 15 24 | 6 26 | 131,176| 8,373 Friday | 96 | 16 0 | 6 32 | 127,696| 7,981 Saturday | 96 | 16 0 | 6 20 | 127,536| 7,971 Sunday | 96 | 15 18 | 6 4 | 125,487| 8,092 | +----------------+----------------+--------+--------- | | 103 12 | 43 14 | 857,667|8,300[18] =========+=======+================+================+========+=========
[18] Average proportion of gas from a chaldron of coal.
Coals, decomposed, 103 chaldron 12 bushel, at £ 2. 11_s._ 6_d._ the chaldron, (27 Cwt.) £ 266 2 0
Small Coal, 43 chaldron, 14 bushels, used for fuel, at £ 2. 2_s._ the chaldron 91 2 4
Wages of two additional workmen (not required had the retorts been worked at eight hours charges,) at £ 1. 16_s._ each man, the week 3 12 0 ----------- Total expenditure, £. 360 17 0
Coke, 103 chaldron, 12 bushel, at £ 1. 7_s._ the chaldron £ 139 10 0
Breeze, or small coke, 6 chaldron, 9 bushels, at 18_s._ the chaldron 5 12 6
Ammoniacal liquor, 1864 gallons, at 1¹⁄₂_d._ the gallon 11 13 0
Gas, 857,667 cubic feet, at 15_s._ the thousand cubic feet 643 5 0 ---------- Total for products, £ 846 10 6