THE WEIGHT TEST FOR STEAM ENGINES.
In view of the proposed test of Steam Fire Engines before the Convention of Chief Engineers at Washington this fall. I desire to say a few words relative to the weight test, which was one of the requirements at the Centennial Exhibition.
The shortest road from one point to another is a straight road. The best road to Washington (other things being equal) is a straight road. An Engine that is most powerful, and at the same time the lightest and equal in the other requisites of a good Engine, is the best. An Engine of 20power so constructed that two average horses can take it to the fire is better than one of 25-power that is so heavy that two horses cannot haul it. It is not a good statement to say the Engines that use the lowest steam (other things being equal) is the best, because pressure of steam is in no sense a ruling consideration, while weight and power are the ruling points. The first contract made in this city for a Steam Fire Engine had but two stipulations of any consequence ; first, it should not weigh, ready for duty, over 5000 pounds ; and, second, it should be capable of throwing a lX-inch steam as tar as any first-class Hand Engine in the city.
The first builders were compelled to meet the matter of power and weight, and were successful in securing the confidence and good will of the Volunteer Departments just in proportion to their success in producing the most powerful Engine according to its weight.
It is to-day just as important a question as twenty years ago, and is constantly acted upon by manufacturers who copy the lightest that will answer the purpose. There are few builds of Engines to-day that are as well proportioned as some that were built twenty years ago. To show the desire for all the power it is possible to take to the fire, I may mention the fact that arrangements are made by which four Engines may be arranged to play through one nozzle, showing that it is desirable to have Engines of four times the power they’now have. Seif-propellers are used to get more power to the fire than can betaken by two horses.
The railroad locomotive that has the largest amount of power per weight (other things being equal) is the best. I know an able and distinguished engineer who has mathematically demonstrated to his own satisfaction that a superfluous pound in weight in a locomotive would cost, to carry during the life of it, a pound of gold. This rule holds good as regards shipping. The largest displacement with the least weight of ship is the best—for it will carry more. The builder that will reduce the weight of the shell boat by ten pounds will secure the orders. For ships and locomotives too heavy retribution comes gradually in the form of reduced profits, but in the case of Steam Fire Engines it comes sooner in the form of broken-down horses, and is always liable to come now in the form of late arrivals at fires, and sometimes in a failure to come at all. The work demanded of a Steam Fire Engine compels the builder to add every foot-pound of power to his pumping capacity that is possible and, at the same time, consistent with its portability. I sometimes think, in this connection, ol the wise woman who wrote a cook book, and who, before telling how to cook a hare, says : “ First catch your hare.” First take your Engine to the fire, and take one with as much power as you can haul at a reasonable speed, with a tolerable certainty that you will arrive and not get stalled on the way. That is, first the weight question ; second, the amount of power question.
NEW YORK, May 7th.