GAS-WORKS 619 



These impurities, which are encountered in almost all coal-gas now used, are the 

 principal if not the only source of the unpleasant symptoms experienced by many 

 sensitive persons in rooms lighted with gas. It is also owing to the sulphurous acid 

 generated during the combustion of these impurities that the use of gas is found to 

 injure the bindings of books, and impair or destroy the delicate colours of tapestry : 

 therefore the production of gas free from these noxious sulphur-compounds is at the 

 present moment a problem of the highest importance to the gas-manufacturer, and 

 one which demands his earnest attention. 



The high sanitary position which gas takes, with regard to the production of a 

 minimum amount of carbonic acid and heat for a given amount of light, ought to 

 stimulate the manufacturer to perfect the process, by removing all sulphur-compounds, 

 and attaining the most desirable composition, so that this economical, and if pure, 

 agreeable and sanitary light, may contribute to our domestic comfort to a much greater 

 extent than it has hitherto done. 



FOP the Royal Coal Commission (1869) circulars were issued to all the gas com- 

 panies in the United Kingdom, public and private, so far as those could be ascertained. 

 Eeplies, giving very full information, were received from 1,024 works. These used, 

 in 1867, 3,612,954 tons of coal, and in 1868, 3,811,981 tons: the increase being 

 about 200,000 tons for each year. This has been confirmed by subsequent enquiries, 

 so that in 1873 the same number of gas-works would have used about 4,800,000 tons 

 of coal. Those works which are not included in the return from which this quantity 

 is estimated, will have used above 2,500,000 tons ; consequently, we may estimate the 

 quantity of coal now (1874) used is 7,300,000 tons. 



The number of cubic feet of gas produced from each ton of coal, according to the 

 returns referred to, were 8,300. The total produce of gas would therefore be 



60,590,000,000 cubic feet. 



The following description of the Brighton and Hove General Gas Company's Works, 

 Portslade, Sussex, by Mr. John Biret Paddon, as it embraces the most recent improve- 

 ments, (the paper was read on Februarys, 1874, at the Institution of Civil Engineers), 

 cannot fail to form a useful appendix to this article : 



' The site of these works was the wildest, most level, and highest part of a tract of 

 shingle lying between the sea and the canal forming the eastern entrance to Shoreham 

 Harbour. This shingle was formerly arrested in its eastward movement by the 

 entrance works to the harbour ; but since the construction of the present westerly 

 entrance, it had been greatly wasted by the sea. Between 1865 and 1870, in front of 

 the site of the gas-works, the high-water mark at ordinary spring tides advanced land- 

 wards 100 feet ; and at high tides, during strong gales of wind, the waves broke over 

 the greater portion of the land referred to. To obtain a deposit of shingle along the 

 sea front as a protection, and to prevent the lighter portions of the waves passing over 

 the bank, two groynes were constructed, one, in accordance with local custom, being at 

 a right angle to the shore. With groynes so built there was an invariable scour and 

 waste on the lee side, so that a repetition of such groynes along the coast to be pro- 

 tected became a necessity. The second groyne was designed to prevent this destructive 

 action, and was projected towards the east at an angle of 45 to the shore. The 

 result has been satisfactory, for soon after its completion a large bank of shingle 

 accumulated on the east side, where it had since remained. A breastwork had also 

 been constructed of creosoted Swedish timber ; and although several times exposed to 

 the coincidence of a high tide and a strong gale of wind, it has proved a suitable and 

 efficient protection. At a depth of 14 feet the ends of the piles entered a stratum of 

 sand and gravel of great density and holding -power. A supply of water had been ob- 

 tained by sinking an iron cylinder to a depth of 50 feet below the ground line. The 

 water from the chalk at this point held in solution 500 grains per gallon of salts (sea- 

 water containing 2,700 grains per gallon), and was available for most of the purposes 

 of the works, except for drinking. The water-tanks over the pump-room furnished 

 storage for 20,000 gallons of water a quantity sufficient for ordinary operations to an 

 extent represented by the consumption of 100 tons of coal. Excellent material for 

 concrete was found in the excavations, and the foundations of the walls were extended 

 so as to make the proportion of the weight of the superstructure to the bearing surface, 

 15 cwt. per square foot. The concrete bed under the retort benches was 7 feet 6 inches 

 thick. 



1 The retort-house was 284 feet 6 inches long and 80 feet wide, inside measurement. 

 The chimneys were constructed with the lower parts of brick and the upper parts of 

 wrought iron, and were sufficiently light to be placed on the benches, so that no floor 

 space was occupied. They were 71 feet 6 inches high, 3 feet square at the bottom, 

 and 3 feet in diameter, at the top, the least sectional area giving one square inch for 

 each lineal foot of retort, a proportion which had been satisfactory. In consequence 



