"What San Francisco wants more than anything else is cheap power for small factories," said Tom Trebell, foreman of the underground Telegraph and Telephone Company.

      Mr. Trebell was formerly of the Government Postal and Telegraph Service in London, and is an enthusiast on the subject of pneumatic power. He is an eminently practical man, and there is nothing of the visionary or crank about him.

      Said he: "There is no city in the United States where the pneumatic system would work so well as in San Francisco. The reason is that coal is very dear, and insurance rates high. As soon as a man starts a small factory he finds the expense of steam power eating up all his profits.

      "There has been considerable talk of late about the construction of a complete pneumatic system for this city, but so far it has all ended in talk.

      "Four months ago I applied to the Supervisors on behalf of the Pneumatic Company just organized for power to put down pipes for the transmission of compressed air, but for reasons not explained to me the thing has been laid over indefinitely.

      "Let me show you what could be done if such a plant was established four or five miles out of town and the pipes laid down in this city just gas and water pipes are laid down.

      "Every man who wanted power in his business, from half a horse to 100, could make connection with a pipe and use just as much or as little as he wanted. The consumption is registered by a meter. There would be no insurance to pay, no wear and tear of boilers, no fumes, no foremen or skilled engineers required and no danger of any kind. Compressed air is as easy to serve as water from the mains. These conditions are just the thing needed by a man who wants to ran a small factory, to turn a lathe in his own room or to run a small dynamo for electroplating or other purposes.

      "Look at the cheapness of the thing. Coal cannot be bought In this city for less than $6 a ton and it takes four and a half pounds to produce one horse-power. With a large power-house out in the suburbs and using coal in large quantities the production of one horse-power would require only one and a half pounds of coal. It is a simple proposition to compress and store up the air in receivers, whence it can be drawn just as illuminating gas is drawn — in any quantities required.

      "Eight-inch pipes could be laid down just as eight-inch water mains are laid down. There would be no danger of explosion. Don't you know that the pressure on the water mains of the city is equal to fully 65 or 70 pounds to the square inch? The pressure in the pneumatic pipes would be only about 90 pounds.

      "With this pneumatic power small pipe lines could be laid down for the rapid dispatch of light packages, messages, etc. There is an apparatus of this kind now in use at the Palace Hotel, and in New York City messages are sent in in instant by the pneumatic dispatch to points which messengers would take an hour to reach."