Among the many modifications of the bicycle as used to-day may be mentioned the drop frame, which has made cycling possible for ladies, the tandem, for two riders, the sextet or octet, carrying six or eight riders and resembling a centipede in movement and an express train in speed: the ice velocipede, in which two runners are combined with a spiked driving wheel, and the hydrocycle, or water velocipede, in which the drive wheel, formed with paddles, is used to propel a buoyant hull through the water. In point of speed there seems to be no limit to the bicycle. In a test made on the Long Island Railroad in the summer of 1899 between a wheel and an express train, the bicyclist, riding on a plank road between the rails and protected behind the train by a wind break, covered a mile in 57⅘ seconds, and while going at top speed of more than a mile a minute, overtook the train, was caught by his friends on a rear platform and pulled on board, bicycle and all. This is the first instance on record of overtaking and boarding an express train going at the rate of sixty-four miles an hour, and yet it is said that the rider (Murphy) was not doing his best. Nearly 5,000 patents have been granted on velocipedes and bicycles. Most of them were for bicycles which, as improved to-day, are not only as fleet as the birds, but almost as countless in numbers. It is estimated that in 1889 the total product of bicycles in this country reached 200,000 machines annually. In 1892, after the general adoption of the pneumatic tire, a great increase followed, which has grown from year to year until in the year 1899 a conservative estimate for the output in the United States is 1,000,000 wheels annually, worth from thirty to fifty million dollars. Each bicycle tire takes about two pounds of pure rubber, or four pounds to the wheel. The annual output in wheels consequently consumes about 4,000,000 pounds, or 2,000 tons of rubber. Ten years ago there were not more than twenty-five legitimate manufacturers of bicycles in the United States. In 1897 there were over 200 concerns in the business. It is estimated that there are to-day between 150 and 155 regular manufacturers, exclusive of the mere assemblers of parts. The Pope Manufacturing Company, which occupies the leading place, employed in 1888 about 500 hands. To-day their shops give employment to 3,800 workmen, which furnishes a significant object lesson as to the importance and growth of the industry.