"SUNLIGHT " GAS ; A NEW ILLUMINANT.

New Zealand Tablet, Volume XXIV, Issue 51, 23 April 1897, Page 29

" SUNLIGHT " GAS ; A NEW ILLUMINANT.

On Tuesday, February 23, there was a demonstration of the merits of the new gas acetylene at the Sunlight Gas Company's works, 18 and 19 Wellington quay, Dublin. The system under which the gas is produced by the company is the invention of Mr. Robert Goodwin, 24 Exchequer street. Mr. Goodwin came to Dublin close on twenty years ago, and set up business as an electrician. When acetylene gas came into notice some years ago he began experimenting with it, and has now patented a process which it is claimed produces a perfectly pure acetylene gas. The gas is produced by bringing calcium carbide in contact with dilute sulphuric acid when the lime is " slacked " and evolves the acetylene and carbonic acid gas. It brings away with it certain impurities composed largely of cupric compounds and arsenic, and this has hitherto been an insuperable difficulty to the use of the gas except |for experimental purposes. The bye products are deposited in the pipes and quickly clog the burners, and they are by no means healthy in a closed room. Mr. Goodwin directed his attention to purifying the gas, and he has succeeded in inventing a process which seems to produce the desired result. The apparatus of the production and purification of the gas is a simple one. The dilute sulphuric acid — one part of acid to seventeen of water — is contained in a cylinder. Below is another cylinder, in which is placed the carbide of lime, a maximum of lOlbs. When the dilute acid is admitted to this cylinder the gas is produced and escapes through a third and smaller cylinder, filled with a preparation of sulphate of copper. The copper removes the impurities which are discharged at the base f the cylinder, and the gas makes its way into the gasometer. Once the apparatus is set going its working is automatic, and when the gasometer is filled the supply of acid to the calcium cylinder is stopped. With ten minutes' working sufficient gas is produced to light an ordinary house at night. The gas, though not so powerful an explosive as ordinary gas, will, like it, work a gas engine. The bye products consist largely of carbonate of lime with some copper.

The main difficulty at present is the scarcity of carbide of lime. It is manufactured from ordinary limestone by heating the lime to incandescence in an electric furnace with carbon rods. Its scarcity is due solely to the fact that it has not hitherto been made on an extensive scale. The company hope to remove that difficulty by procuring its manufacture in disused waterniills through the country, where limestone is to be had in the neighbourhood. This would set the mills of Ireland going once more. The present price of the carbide of lime is £16 per ton. The promoters claim that at that price the cost of the gas compares favourably with that of other illuminants, and they are confident that when its manufacture is extensively carried on the price of the carbide of lime will be less than an eighth of what it is now. They are in communication with mill owners through the country with a view to having mills now idle in limestone districts opened for its manufacture.

A large number of guests accepted the invitation to witness the demonstration. The gas which was produced from a single set of cyclinders lit thirty gas lamps in the factory and drove a gas engine by which were driven three shafts working machinery to be used for the manufacture of the plant for the making and storing of the gas.

Mr. Goodwin explained the merits of the invention. The gas, he said, was odourless and smokeless. It consumed little oxygen, and therefore did not use up the air of a room. It was fifteen times more powerful than coal gas. It burned with a steady white light. While oil gas or coal gas would explode on being mixed with 6 per cent, of oxygen, acetylene would not explode with less than 12 per cent, of oxygen. He exhibited the apparatus on which he had experimented in making his invention and showed the purified and the unpurifled gas working together. He showed the gas lighting in a globe, which was covered in above and below with tin, to show that it would stay alight in almost a vacuum, and that the consumption of oxygen was very little. He demonstrated the smokelessness of the flame by holding a piece of white opal a little above it when there was no perceptible trace of blackening. In addition to its powerful light he claimed that it possessed great power of

penetrating fog, and produced ft light of 12 burners, each of 60 candles, or 600 candles in all, which was exhibited through the lens of a ship's light. The bye products would be useful in various ways. They would be brought back by the company for the copper that they contained and would be of value as manure for land. Mr. Goodwin was frequently applauded. In the original apparatus on which Mr. Goodwin experimented his gasometer consisted of an indiarubber football bag.