��Popular Science Monthly
���foot searchlight throws a questioning shaft of light into the depths below. Close at hand is the Mt. Lowe astronomical observa- tory, which is opened sev- eral evenings in the week to visitors.
��Three levels of track are visible in the zig-zag course up the precipitous mountain side
��Hairpin Curves on a Mountain Trolley Line
THERE is an electric trolley trip up the face of Mount Lowe in Southern California, which, so Europeans have said, equals in thrills and actual interest any of the Alpine or similar jaunts in Europe.
The start is made in an ordinary surface car, which tackles the massive base of the Sierra Madre range by a succession of violent curves, then pur- sues at a modified clip a series of hairpin turns, which are perfectly safe, although it seems that the car must be hanging on by its very eyebrows at times.
At one particular point in the journey, where the car weaves in and out as it (limbs its zig-zag course up the mountain side, three cars may be seen at one time, one directly above the other on the various levels.
I-'ar to the south, as the car ascends, the blue chain of the Temecula Range rises up from the valley. Villages, farms, ranches take on a strangely dissembled and isolated appearance.
'i^he last stop of the car is made at Echo Mountain, where at night a five-
��How an Automobile-En- gine Tests Water-Mains BY means of a centrif- ugal pump driven by an automobile-engine new water-mains are being test- ed in Chicago. The work was formerly done by a triplex pump driven by a gasoline-engine, all mount- ed on a wagon. As most of the pipe-laying is in the outskirts of the city a twenty-five mile drive with a team at six dollars a day to cover one job was not infrequent.
With the new automobile apparatus it is now possible to cover four or five jobs per day in difTerent parts of the cit\'. The number of tests has been increased one hundred and fifty per cent, and practically all jobs are tested. The pump was specially designed for the purpose and rests in a horizontal position. It is driven by the truck through an extra sprocket and a silent chain without any reduction from the speed of the engine. Two men make the tests. One operates the engine and the other reads the meter.
���The automobile engine drives a centrif- ugal pump, testing water • mains in a minimum of time