Industrial and commercial Industry activity is mainly centred at the Peiraeus, where and corn- 8 cloth and cotton mills, cognac distilleries, 14 steam coerce.
The steam is passed through the valve and emerges at the pressure required generally from 3 lb upwards.
Generally steam from the boiler is admitted direct to the low-pressure cylinder through a reducing valve, and valves and devices are used to prevent the steam so admitted acting as a back pressure on the high-pressure cylinder.
In 1788 the first woollen mills in New England were established at Hartford, and about 1803 one hundred merino sheep were imported by David Humphreys, who in 1806 built a mill in that part of Derby which is now Seymour and which was practically the first New England factory town; in 1812 steam was first used by the Middletown Woollen Manufacturing Company.
On the esplanade stands an obelisk to Henry Bell, the pioneer of steam navigation, who died at Helensburgh in 1830.
It is then oxidized to anthraquinone by means of sodium dichromate and sulphuric acid in leaden vats, steam heated so that the mixture can be brought to the boil.
Bituminous coal, natural gas and oil abound in the vicinity; the river provides excellent water-power; the borough is a manufacturing centre of considerable importance, its products including iron and steel bridges, boilers, steam drills, carriages, saws, files, axes, shovels, wire netting, stoves, glass-ware, scales, chemicals, pottery, cork, decorative tile, bricks and typewriters.
There is a harbour at Castro, and steam flour-mills, foundries and tanneries have been established.
Its once famous tanneries have lost their importance, but the manufacture of linen has increased; it has also steam flour-mills, distilleries, manufactories of soap and of iron implements.
Saturated steam is steam in contact with liquid water at a temperature which is the boiling point of the water and condensing point of the steam; superheated steam is steam out of contact with water heated above this temperature.