SINUS, Fr. See [Line] for its geometrical acceptation.
Sinus, in English, signifies a bay of the sea, an opening of the land; any fold or opening.
SINUSOIDE, Fr. A geometrical curve, which has been imagined by Monsieur Belidor, for the purpose of balancing or preserving the equipoise of a drawbridge. See Science des Ingénieurs, liv. iv. See likewise the specific construction of this curve as explained by the marquis de l’Hopital, in a book intitled, Acta Eruditorum, published at Leipsic in 1695; and demonstrated by M. Bernouilli, who discovered that this curve was nothing more than the [epicycloid], which see.
SIPHON, (Syphon, likewise Ciphon, Fr.) In hydraulics, a crooked tube, one leg or branch whereof is longer than the other. It is used in the raising of fluids, emptying of vessels, and in various hydrostatical experiments.
SIRKAR, Ind. The government.
SIROC. From Sirius, the dog-star. The wind, which we call south-east, is so called in Italy.
To SIT. In a military sense, to take a stationary position; as, To sit before a fortified place; to lie encamped for the purpose of besieging it. The French use the word asseoir as an active verb with respect to military matters, viz. asseoir un camp, to pitch a camp. Il assit son camp hors de la portée du canon de la ville; he pitched his camp out of the range of the town’s cannon.
SIXAIN. Sixth, Sexagena, in war, an ancient order of battle, wherein six battalions being ranged in one line, the second and fifth were made to advance, to form the van guard; the first and sixth to retire to form the rear guard; the third and fourth remaining to form the main corps. The word is derived from the French, which signifies the same thing. The sixain order of battle may be formed with all the battalions whose number is produced by the number six. Twelve battalions, for instance, may be ranged in order of battle, by forming two sixains, and eighteen battalions, ditto by forming three sixains, and so on progressively.
To SIZE. In a military sense to take the height of men for the purpose of placing them in military array, and of rendering their relative statures more effective. In all infantry regiments the sizing begins from flanks to centre, the tallest men being placed upon the right and left of the several companies in the front rank, and the shortest in the centre and rear ranks. By the old cavalry discipline the flank troops of a squadron must be sized in the following manner: That of the right flank, from right to left; that of the left flank, from left to right; the centre one from centre to flanks; the tallest man must, of course, be always in the part where the sizing begins, excepting the corporals, one of whom must be on each flank of the front rank of the troop, covered by a clever soldier in the rear rank. If there be only two troops in a squadron, they size the right from the left, and the left from the right flank. The modern practice now is to size all troops from the centre, beginning by sizing from the right, doubling and countermarching a rank.
SKEAN, Celtic. A knife. This word is sometimes written skeen, or skeine. It signifies a weapon, in the shape of a small sword or knife, which was anciently worn by the Irish.