When the corn is much laid and entangled, it is impossible to use the common scythe, even with a cradle. This has probably suggested a scythe to be used with one hand, while a hook in the other gathers the straggling corn. The most perfect of these scythes is called the Ilainault scythe, from a province of that name in Belgium, where it was first noticed. It is commonly used in different parte of the Con tinent. The Hainault scythe is swung by the power of the wrist principally. It does not cut the straw by so oblique a stroke as the common scythe, but rather as a bill-book or axe would do, meeting the straw nearly at right angles. The book collects a small bundle, which is severed at a stroke, and the left foot assists in holding what is cut and rolled together with the hook, in the hollow of the blade. It is thus laid aside, and fit to be tied up. This instrument is a great improvement on the English fagging-Look, which is used in the same manner, the left arm of the reaper acting the part of the hook; but as the handle is inserted in the plane of the blade, it causes the reaper to stoop low, which is fatiguing to the loins, especially of elderly people, who can more readily reap with the Hainault scythe.
The scythe is an instrument which should be more generally intro duced In harvest, and experience has proved that it had many advantages over the sickle or reaping-hook. [Ilaevesr.] SEA and OCEAN are terms by which the whole volume of water is designated which occupies the lower portion of the surface of our globe, and thus separates the solid and more elevated masses which are called land, and which rise above the level of the sea.
Sea-water has a salt and somewhat bitter taste, and in its natural state is unfit for drinking or for culinary purposes. Its specific gravity is about 1.0277, rain-water being 1.0000. Tho water of closed seas into which many rivers fall is lighter, as that of the Baltic, which is and that of the Black Sea. But the water of the Mediter ranean is more salt than that of the Atlantic Ocean. In those parte of the ocean which approach the poles the water is of less specific gravity than in those parts which lie towards the equator, which may be due to the melting of the enormous masses of ice which are found in the higher latitudes.
Sea-water has repeatedly been analysed ; the latest results are stated under SODIIIII. That of the Baltic contains only 118 per cent. of salt, but the water of the Mediterranean contains 918 per cent. ; the former being considerably below and the latter somewhat above the average of the oceanic water. The sea is therefore a weak brine, from which the salt may be extracted by the beat of the sun and dryness of the climate.
Besides mineral substances, sea-water contains a slimy fetid matter, which imparts to it a nauseous taste, and which is probably the pro duce of the decomposition of animal and vegetable substances, which abound in the sea. It has been observed that the sea-water, when not agitated for a long time, is very subject to pass into a certain state of putrefaction, and in that state it exhales very unpleasant odours, which are a real nuisance to the seaman. It is likewise known that some low
coasts between the tropics are subject to diseases, which are attributed to the miasma arising from the sea after a long continuance of calm weather.
It has often been maintained that sea-water has no colour, but it is well known that the sea at a great distance from the Land has an exceedingly fine ultramarine tint, which cannot be considered due to reflection from the atmosphere, as the colour of the sea h frequently of a deeper hue than that of the sky, and does not change even when the sky is covered with clouds. This colour undergoes some changes in shoals, where it is modified by the colour of the matter which forms the bottom. The greatest variety in the colour of the sea seems to occur in the Greenland Sea, between 74' and 80' N. lat., where it varies from ultramarine to olive green, and from the most perfect transparency to deep opacity. The green colour is liable to changes in its position, but still it is always renewed near certain eituations from year to year. According to Scoresby, from whom we take this account, it frequently constitutes long bands or streams, lying north and south, or north-east and south-west, but of various dimensions, sometimes extending two or three degrees of latitude in length, and from a few miles to ten or fifteen leagues in breadth. This occurs very generally about the meridiau of London, and the whales chiefly feed in this green-coloured water. When examined by Scoresby, it was found to be replete with minute animals, principally Meduste, to which its colour was due.
The transparency of the sea-water seems to be connected with its colour. It is much greater than that of river-water, which contains much heterogeneous matter in suspension. It has been said that the light penetrates to about the depth of 60 feet only, but this is a vague estimate, requiring much qualification ; some rays certainly penetrate much deeper. This transparency of the sea-water increases with the distance front the shores, and is generally greater in the higher than in the lower latitudes, which may arise from the circumstance that the number of organic substances in the sea is much greater in warm climates. But there are many remarkable exceptions to the last mentioned fact. Some parts of the sea between the tropics are dis tinguished by the transparency of their waters, especially the Caribbean Sea, where zoophytes and sea-plants, though growing on a bottom twenty or thirty feet deep, appear to be near enough to the surface to be plucked by a person in a boat ; indeed some navigators affirm that the bottom of the sea may be seen at the depth of 150 feet. In the northern seas indeed it is asserted that the bottom may be seen at the depth of from 900 to 500 feet.