The Great World's Fair Searchlight, which is now so well known from its operation on Echo Mountain, first became famous at the World's Fair, Chicago, where it excited great interest, and surpassed all other exhibits in its line. After the Fair, it was taken to San Francisco and exhibited at the Mid-Winter Fair, where it delighted thousands from the Bonet electric tower, 264 feet high. When the Mid-Winter Fair was over, Professor Lowe purchased it and removed it to Echo Mountain, where it rests at an altitude of 3,500 feet above sea level. Until this great searchlight was established in its present location its powers could not be brought out on account of its location so near the general level of the surrounding country. Here, however, it is so located that its rays can be seen for 150 miles on the ocean, and the most distant mountain peaks can be made visible by its penetrating rays. The beam of light is so powerful that a newspaper can be read for a distance of thirty-five miles, and its full sweep illuminates the peaks of mountains which are hundreds of miles apart.

It is of 3,000,000 candle power, and stands on a wooden base, built in octagon form, which has a diameter of about eight feet. The searchlight itself stands about eleven feet high, and its total weight is 6,000 lbs., yet it is so perfectly mounted and balanced that a child can move it in any direction.

The reflecting lens is three and a quarter inches thick at the edges and only one-sixteenth of an inch at the center, and weighs about 800 lbs. The metal ring in which the lens is mounted weighs 750 lbs., the total weight of lens, ring and cover being about 1,600 lbs. This great mirror is mounted at one end of the big drum, the outer end of which is furnished with a door, consisting of a narrow metal rim, in which are fixed a number of plate glass strips five-sixteenths of an inch thick and six inches wide. The value of this great searchlight in meteorological work has already been demonstrated on a small scale. When there is moisture in the atmosphere, and varying wind-currents, the light turned upwards discovers the directions in which the wind is conveying the clouds, and aids in revealing the conditions that cause these variations.