ing-machine. The steam-plough has not yet been introduced extensively, but it will doubtless make another revolution. The progress made in the drainage of land by pipes, in the drying of fruits and vegetables by hot air, and the canning of fruits and meats, all are important aids to agricultural industry. The breeds of farm-animals have been greatly improved. The Ayrshire, the Durham, the Jersey, and the Devon, the Cotswold, the Southdown and the Cheviot, the Chester and the Berkshire, the Clydesdale and the American trotter, have been either started, or for the first time introduced into extensive use, in the steam age.
The miner has adopted dynamite and other explosives stronger and safer to handle than the charcoal-powder, and can, at the same time, hold and strike the small drill, whereas the large drill needed for the weaker powder required one man to hold the drill while another was striking. Steam not only hoists the ore and pumps the water, but sometimes drills the rock. The method of stoping toward the shaft has been introduced. More important still is the general education of the superintendents in engineering and chemistry. The processes of separating gold and silver from the earthy and rocky matter which hold them in a state of nature are new in their principal features.
All the prominent mechanical occupations have felt the influences of our progressive time, and many have been added to the list. Nearly every labor-saving machine has called a new trade into existence. The builders of stationary engines, of locomotives and of railway-cars, the boiler-maker, the steam, the railway, and the gas engineers, the gas-fitter, and the manufacturer of chemicals, are a few out of many. Planing and moulding machines, and circular and band saws, wire ropes and iron bridges, "balloon" house-frames, fastened together with nails, and without the old style of mortices and tenons, and machines to make cut-nails and wood screws, have had much influence in mechanical business. If steel pens had not come into use as a substitute for quills, the supply of which would have been entirely inadequate to the scribbling demands of the present day, education might have felt a check. The steam-press, the turbine-wheel, the type-casting machine, lamp-chimneys which secure better light with less smoke, kerosene-lamps, cleanly stearine-candles instead of the dirty tallow, are all to be credited to the steam age.
The railroads and the steamboats have covered the land, the rivers, and the lakes of Europe and North America with the beneficent network of their routes, and have given a new life to commerce. The exports of Great Britain in 1770 amounted to $65,000,000, and in 1870 to $1,220,000,000. In the same period the measurement of the shipping owned in that country increased from 550,000 to 7,100,000 tons, and that of the shipping entered in a year from 890,000 to 18,000,000 tons. The amount insured rose from $850,000,000 to $6,800,000,000.
