OFF 



OIL 



dusivp. .v'ho are thus denominated in con- 

 tr.i -!" .notion to warrant officers, who 

 a:> ^pointed by the colonel's or captain's 

 warrant, as quarter-masters, sergeants, 

 corporals, and even chaplains and sur- 

 geons. 



OFFICERS, fold, are such as command 

 a whole regiment, as the colonel, lieu- 

 tenant-colonel, and major. 



OFFICERS, general, are those whose 

 command is not limited to a single com- 

 pany, troop, or regiment ; but extends to 

 a body of forces, composed of several 

 regiments : such are the general, lieu- 

 tenant-general, major-generals, and briga- 

 diers. 



OFFICERS, staff, are such as, in the 

 King's presence, bear a white staff, or 

 wand ; and at other times, on their going 

 abroad, have it carried before them by a 

 footman, bare-headed : such are the Lord 

 Steward, Lord Chamberlain, Lord Trea- 

 surer, &c. 



^ The white staff is taken for a commis- 

 sion, and at the king's death each of these 

 officers breaks his staff over the hearse 

 made for the king's body, and by this 

 means lays down his commission, and 

 discharges all his inferior officers. 



OFFICERS, subaltern, are all who ad- 

 minister justice in the name of subjects : 

 as those who act under the Earl Marshal, 

 Admiral, &c. In the army the subaltern 

 officers are the lieutenants, cornets, en- 

 signs, sergeants, and corporals. 



OFFICIAL, by the ancient law, signifies 

 him who is the minister of, or attendant 

 upon, a magistrate. In the canon law, 

 it is especially taken for him to whom 

 any bishop generally commits the charge 

 of his spiritual jurisdiction ; and in this 

 sense there is one in every diocese called 

 offidalis priucipalis, whom the law r s and 

 statutes of this kingdom call chancellor. 

 32 Hen. VIII. 15. 



OFFING, or OF FIN, in the sea-lan- 

 guage, that part of the sea a good dis- 

 tance from shore, where there is deep 

 water, and no need of a pilot to conduct 

 the ship : thus, if a ship from shore be 

 seen sailing out to seaward, they say, she 

 stands for the offing : and if a ship, 

 having the shore near her, have another 

 a good way without her, or towards the 

 sea, they s'ay, that ship is in the offing. 



OFF-SETS, in gardening, are the 

 young shoots that spring from the roots 

 of plants; which being carefully se- 

 parated, and planted in a proper soil> 

 serve to propagate the species. 



OFF-SETS, in surveying, are perpendi- 

 culars let fall, and measuring from the sta- 



tionary lines to the hedge, fence, or ex- 

 tremity of an enclosure. 



OGEE, or O. G., in architecture, a 

 moulding, consisting of two members, the 

 one concave, and the other convex ; or, 

 of a round and a hollow, like an S. 



OGIVE, in architecture, an arch, or 

 branch of a Gothic vault ; which instead 

 of being circular, passes diagonally from 

 one angle to another, and forms a cross 

 with the other arches. 



OIL. The general character of oils are 

 combustibility, insolubility in water, and 

 fluidity. From the peculiar properties of 

 different oils, they are naturally divided 

 into two kinds ; fixed or fat oils, and vo- 

 latile or essgitial oils. The fixed, or fat 

 oils, require a high temperature to raise 

 them to the state of vapour, a tempera- 

 ture above that of boiling water ; but the 

 volatile, or essential oils, are volatilized 

 at the temperature of boiling water, and 

 even at a lower one. Both the volatile 

 and fixed oils are obtained from plants, 

 and sometimes from the same plant ; but 

 always from different parts of it. While 

 the seeds yield fixed oil, the volatile oil is 

 extracted from the bark or wood. One of 

 the most distinguishing characteristics of 

 the fixed oils is, that they exist only in 

 one part of the vegetable, in the seeds. 

 No trace ot fixed oil can be detected in 

 the roots, the stem, leaves, or flowers of 

 those plants, whose seeds afford it in 

 great abundance. The olive may seem 

 an exception to this. The oil which it 

 yields is extracted, not from the seeds, 

 but from its covering. Among plants too, 

 fixed oils are only found existing in those 

 whose seeds have a peculiar structure. 

 The seeds of plants kave sometimes one 

 lobe, in which case they are called 

 " monocotyledonous" plants ; and some- 

 times they have two, when they are de- 

 nominated " dicotyledonous." The 

 formation of fixed oil in plants is exclusive- 

 ly limited to the latter class. There is 

 no instance of fixed oils being found in the 

 seeds of plants which have only one lobe. 

 Those seeds which yield the fixed oils 

 contain also a considerable portion of 

 mucilage, so that when such seeds are 

 bruised and mixed with water, they form 

 what is called an emulsion, which is a 

 white fluid, containing a quantity of the oil 

 of the seed mixed with the mucilage. 

 Fixed oils are extracted from the seeds 

 of a great number of plants. Those 

 which yield it in greatest abundance are, 

 the olive, thence called olive oil ; the 

 seeds of lint, and the kernels of almonds, 

 called linseed, or almond oil. Fixed oils 



