J 



Nov. 30, 1888.J 



SCIENTIFIC NEWS. 



561 



incapable of direct solution. It is, however, open to 

 indirect attack. When carbon is heated in a current of 

 partially dried oxygen, a slow combustion goes on, and, 

 taough the oxygen is in excess, both oxides are produced. 

 The amount of monoxide, however, is twenty times the 

 mount of the dioxide. Experiments also show that this 

 occurs at temperatures at which dry carbon dioxide is 

 not reduced by carbon. The carbon monoxide must, 

 therefore, be produced by the direct union of its elements, 

 its further oxidation being prevented by the dryness of 

 the gases. Confirmatory experiments were performed 

 in which carbon monoxide was found to be produced by 

 the slow combustion of carbon : n air at 440 , a tempera- 

 ture too low for the reduction of the dioxide by carbon. 

 It is probable that the ordinary combustion of carbon 

 goes on in two stages, that carbon monoxide is first pro- 

 duced, and, if circumstances are favourable, this is fur- 

 ther oxidised to carbon dioxide. 



LEEDS GEOLOGICAL ASSOCIATION. 

 [n his inaugural address, Mr. J. E. Bedford, F.G.S., gave 

 an interesting account of Natural gas. He stated that 

 :he earliest record he could find of the discovery of 

 natural gas in America was in Washington county, 

 Pennsylvania, some sixty-five years ago. Some work- 

 men were making a boring to obtain brine for the manu- 

 facture of salt, when, after obtaining the brine, small 

 quantities of the gas made their appearance, but not in 

 such quantities as to excite curiosity or produce any 

 unusual effects. But suddenly large quantities of the 

 gas rushed out and obliged the men to leave off working. 

 The old account says that " the gas resembled hydrogen 

 to all appearances, and that in effect it is similar to all 

 that species of air that frequently collects in mines, known 

 by the name of firedamp, which all chemists agree is 

 hydrogen." Then an account of an accident is given, 

 which, igniting the gas, illumined the country for miles 

 around. Still no value was attached to this gas, and for 

 years it was allowed to escape into the atmosphere, until 

 some ingenious individual conceived the idea of fixing 

 p : 7>es to the mouth of the well and conveying the gas to 

 the brine pans and boilers as fuel. From this time its 

 e'Snomic value was recognised, and it is now used to a 

 ' ry large extent in many manufacturing districts, and 

 c specially in Pittsburg. In this city it is used for a great 



ariety of purposes, such as warming dwelling-houses, 

 < aoking purposes, heating steam boilers, fuel for blast 

 furnaces, etc. The gas is under considerable pressure, 

 and pipes of only moderate diameter are required to 

 f ipply large quantities of gas. For instance, a 40-horse 



ower boiler is supplied with gas by a 2-inch pipe, the 

 jjs valve, too, being only half-opened. When the boiler 

 is sufficiently heated, and the supply of gas adjusted, 

 then little further attention is required. Mr. Bedford 

 then related an instance showing the great utility and 

 economy of this gas as fuel. Messrs. Jones and Laughlin, 

 i-f Pittsburg, have 72 steam boilers and 90 puddling fur- 

 naces. They turn out per month about 5,900 tons of 

 puddled iron, from Siemens and other furnaces 13,000 

 tons, and of steel 7,300 tons. All this metal was reduced 

 to bars, plates, etc., the steam to run the heavy machinery 

 being produced by the gas-heated boilers. Before 

 the use of gas fuel, the consumption of coal was over 

 300,000 tons per annum. The whole of this vast 

 establishment (where about 5,000 hands are employed) 

 is now fed by a single gas-pipe, 20 inches in diameter, 



the pressure on which is only about 1 lb. on the square 

 inch. The pressure varies somewhat at times, but is 

 under control. The entire concern has been run on a 

 pressure of three ounces to the square inch. The won 

 derful heating power of this fuel is due to the fact that a 

 very large percentage (in some cases nearly 90 per cent.) 

 of it is hydrogen, and, as is known, a given weight of 

 hydrogen will produce in burning three times as much 

 heat as the same weight of carbon. The value of this 

 fuel in establishments of this kind, in comparison with 

 coal, is dependent upon the conditions under which the 

 two fuels can be obtained. It is estimated, however, that 

 there is an average saving of from 60 to 75 per cent., of 

 which one half is represented by the cost of fuel, and as 

 much more by the cost of labour and material. The re- 

 markable purity of this gas is another important feature 

 in its favour, and for this reason it is especially valuable 

 in puddling furnaces, where the iron is very liable to be 

 deteriorated by sulphur, etc., from inferior fuel. There 

 are also large glassworks using this natural fuel, and the 

 owners find that they produce better glass and with 

 greater economy than with any other fuel. In fact, 

 there is not a single manufacturing establishment in 

 Pittsburg of any importance which now uses anything 

 but natural gas as fuel. The number of private residents 

 whoareusing this gas forcooking purposes and for heating 

 their houses, is very large and rapidly increasing. The 

 supply of natural gas is derived from the Palaeozoic strata, 

 although it has been found in newer formations. The 

 Trenton limestone of the Lower Silurian is very produc- 

 tive, although gas in some quantity is found in the shales 

 above the limestone. From these shales, however, there 

 is not a continuous supply, as they are generally in 

 pockets. The difference between a good gas well or a poor 

 one is due to the porosity or density of the Tranton lime- 

 stone. Mr. Bedford here showed three specimens of this 

 limestone. The first example was of a very spongy, 

 porous character, similar in appearance to pumice stone. 

 This was from the Kary well at Findlay, which produces 

 12,600,000 cubic feet of gas every twenty-four hours. 

 The second specimen was porous, but not so much as the 

 first one. This was from the Heck well, in the same 

 neighbourhood, which produces between five and six 

 million cubic feet per diem. The third specimen was a 

 compact, hard limestone, showing hardly any porosity, 

 and was from the Eastern Findlay territory. This well 

 only produces half a million cubic feet per day. These 

 specimens showed most clearly the comparative difference 

 in the porosity and the density of the Trenton limestone, 

 and the relation which these circumstances bear to the 

 flow of gas. What has the Trenton limestone to do with 

 this natural gas ? Is it the source of its origin, or is it 

 only from its porosity a vast passage or natural pipe line, 

 so to speak, for the distribution or conveyance of this 

 enormous volume of gas ? He adhered to the theory 

 that the gas is generated far below the Trenton lime- 

 stone, and it can easily be supposed that with the tre- 

 mendous pressure it is subjected to at its point of origin, 

 it would force its way through the intervening strata 

 until it reached this limestone, and then become dis- 

 tributed through it. The shales and slates above the 

 limestone act as an effectual barrier to its further pas- 

 sage, until, either by natural fissures or by the agency of 

 man, it finds a vent. As to the tremendous pressure 

 alluded to, the well at Canonsberg, Pa., may be men- 

 tioned as having the greatest registered pressure of any 

 in the world. The gas looks like a solid piece of blue 



