Page:Popular Science Monthly Volume 90.djvu/451

This page needs to be proofread.

Popular Science Monthly


��Building a Street Car Line Without Stopping Work or Cars

THERE are streets in con- gested districts of some of our cities where both vehicular and car traffic is so dense that even stone ballast will not prevent the "work- ing" of the railway ties, and as a result the paving in the railway area and adjacent thereto is ruined. To avoid this, the concrete should be used under the ties.

"How can the concrete be put under the ties with the least trouble, expense and in- terruption to car traffic?" A novel way of doing it has been tried out and proved feasible: First, the track work is brought to the correct grade and line, using the ordinary crushed stone ballast under the ties. Then, from a small continuous mixer, placed just far enough from the rail to permit cars to pass, a thin cement grout is conveyed in chutes to the ballast. The grouting mixture is composed of one part cement and two parts sand, at about the consistency of thin cream. By the use of a flexible chute in two sections the work is carried on without the slightest interrup- tion to car traffic. When a car comes along, the first section of the chute is thrown out of service and the second is lowered to the ballast, and so on.


���of the coal

into a recess

���A flexible chute in two sections is used so ir. interrupted while the cement mixture is being

��A Meter for Registering Amounts of Coal Used in Power Plants

XE of the principal fac- tors in the success of a power-plant is the ability to control the quantities of ma- terial used in the production of power. It is neces- sary to know how much water is evapo- rated per pound of coal and just how many pounds of coal should be used for each horsepower. In order to get such statistics, a coal meter has been invented, which con- sists of a recorder driven by the passing of the coal in such a way that its movement is proportional to the rate of flow of the coal. The recorder can be made to register in any units desired.

The meter was designed originally to check up the boiler room performance of a large railway plant in the hard coal fields of Pennsylvania, but it performed its task so satisfactorily that it was decided to build it for general boiler-room use. To install the meter, a rectangular slot or window is cut in the chosen pipe as shown in the illustration. The meter is then inserted "ribbon end" first, and dropped into place. No bolts, screws, rivets or fastenings of any kind are required, as the frame is made with a recess which grips the pipe firmly and prevents the meter from slipping out of place.

The face of the recorder is conveniently located on the outside of the pipe, so that it may be easily read. Thus ac- curate information may be obtained as to how much coal is required for a given amount of energy, and statistics are found that help in estimating the upkeep of the plant.

Other advantages of this type of coal meter are the durability of its construction and the little attention which it requires to keep it in perfect working condition. There is dii( IN n,,t nothing about it to get out

deposited of order.

�� �