The chief exports are linen, whisky, aerated waters, iron ore and cattle.
A dorsal contractile heart, with symmetrical right and left auricles receiving aerated blood from the ctenidia and mantle skirt, is present, being unequally developed only in those few forms which are inequivalve.
The modern distilling plant consists of two main parts termed the evaporator and condenser; in addition there must be a boiler (sometimes steam is run off the main boilers, but this practice has several disadvantages), pumps for circulating cold water in the condenser and for supplying salt water to the evaporator, and a filter through which the aerated water passes.
The aeration of the water is effected by blowing air into the steam before it is condensed; as an auxiliary, the storage tanks have a false bottom perforated by fine holes so that if air be injected below it, the water is efficiently aerated by the air which traverses it in fine streams. After condensation the water is filtered through charcoal.
D, The branchial efferent vessel carrying aerated blood to the auricle, and here interrupting the circlet of gill lamellae.
In the siphon used as a container for aerated waters a tube passes through the neck of the vessel, one end terminating in a curved spout while the other reaches to the bottom of the interior.
When these processes continue for a long time in deep water shut off from free circulation so that it does not become aerated by contact with the atmosphere the water becomes unfit to support the life of fishes, and when the accumulation of putrefying organic matter gives rise to sulphuretted hydrogen as in the Black Sea below 125 fathoms, life, other than bacterial, is impossible.
Its lumber and flour mills are its largest industries, but the following are found: aerated waters and breweries, tent makers, baking-powder manufactories, box manufacturers, brick makers, broom, brushes and carriage makers, cement blocks, manufacturing chemists, chocolate and cigar manufacturers, confectionery, copper plate, cornice makers, engine builders, gas fitters, ink manufacturers, jewelry makers, lime makers, milliners, opticians, paint makers, paper-box makers, photographers, pickle makers, planing mills, pork packers, publishers, pump makers, rubber-stamp makers, sash, door and blind factories, upholsterers, ventilating manufactory, vinegar factories, foundries, wire and fence manufactories.
Agriculture is the staple, but there are chemical, aerated waters, bricks, terra-cotta and other manufactures.
The industries include distilling, the making of aerated waters, and woollen manufactures, and the town is important as a market and distributing centre.