It consists of four hemispherical cups, mounted one on each end of a pair of horizontal arms, which lie at right angles to each other and form a cross.
Assuming this energy to be propagated in hemispherical waves, it is easy to find the quantity per second going through I sq.
By its aid, for example, the whole of the properties a elliptical arches, whether square or skew, whether level or sloping in their span, are at once deduced by projection from those of symmetrical circular arches, and the properties of ellipsoidal and ellipticconoidal domes from those of hemispherical and circular-conoidal domes; and the figures of arches fitted to resist the thrust of earth, which is less horizontally than vertically in a certain given ratio, can be deduced by a projection from those of arches fitted to resist the thrust of a liquid, which is of equal intensity, horizontally and vertically.
Deville's portable blast furnace is very similar in principle to the above, but the body of the furnace is formed of a single cast iron cylinder lined with fireclay, closed below by a cast iron plate perforated by a ring of small holes - a hemispherical basin below forming the air-heating chamber.
Cast iron stills are provided with a hemispherical head or dome, generally attached to the body of the still by bolts, and of sufficient size to allow for any frothing.
If double-bottomed defecators are used in sufficient number to allow an hour and a half to two hours for making each defecation, and if they are of a size which permits any one of them to be filled up by the cane-mill with juice in ten to twelve minutes, they will make as perfect a defecation as is obtainable by any known system; but their employment involves the expenditure of much high-pressure steam (as exhaust steam will not heat the juice quickly enough through the small surface of the hemispherical inner bottom), and also the use of filter presses for treating the scums. A great deal of skilled superintendence is also required, and first cost is comparatively large.
The fruit is a woody capsule of three cells, each containing one large nearly spherical seed, which consists mainly of two large hemispherical cotyledons.
In one side of W a small disk C of gas carbon was inserted, resting on the hemispherical end of a small platinum pin K, about the twentieth of an inch in diameter, held in position by a thin spring A.
Robur, and are dark-brown when ripe; the hemispherical cups are covered with long, narrow, almost bristly scales, giving them a mossy aspect; the fruit ripens the first autumn.
Consider, for instance, the operation of casting a hemispherical bell, in fig.