Page:The New International Encyclopædia 1st ed. v. 01.djvu/557

AMMONIUS. agreement of the teachings of Moses and Jesus, and composed a harmony of the Gospels; Ammonius, son of Hermeas, a Peripatetic philosopher of the fifth century, disciple of Proclus and author of commentaries on Aristotle; Ammonius, the famous surgeon of Alexandria, who lived in the latter half of the first century B.C; Ammonius, the grammarian, pupil of Aristarchus, and his successor as head of the Alexandrian School.

AM'MONOID'EA. An order of tetrabranchiate cephalopods, equivalent in rank to the Nautiloidea. It contains more than five thousand species, all of which are extinct and found in a fossil state in marine rocks of Devonian and Carboniferous, and abundantly in those of Mesozoic age of all parts of the world. The form of the animal in this order is unknown; but from the structure of the shell, it is sup- posed to have a form like that of its only living ally, the nautilus, though of a more delicate construction, and to have been a crawler instead of a swimmer. The shell is coiled in a single plane, with its apex in the centre of the coil, and it is usually compressed into a discoid. This discoid form is in some phylogerontic or senile types of Mesozoic Age changed to a tur- reted, or irregular, or straight shell. The five thousand species of the order are grouped under about five hundred genera and some ninety-eight families, according, chiefly, to the form and mode of development of the so-called suture lines, which are the lines of union of the internal septal walls with the inner wall of the shell. The order is of peculiar interest, in that, of all groups of animals, it furnishes the finest illus- trations of evolution, and the laws of growth and decline, of ontogeny and phylogeny; in other words, of bioplastology. For more particular information and illustrations, see.

AM'MONOO'SUC, A river rising in the White Mountains, New Hampshire, and flowing through Coos and Grafton counties (Map: New Hampshire, G 5). It is 90 miles long, drains an area of nearly 400 square miles, and furnishes extensive water power. It flows into the Connecticut River opposite Wells River, Vermont.

AMMONOOSUC, A river, 40 miles long, rising in the Randolph range of the White Mountains, and draining an area of 252 square miles of Coos County, New Hampshire (Map: New Hampshire, J 3). It flows into the Connecticut below Groveton.

AMMOPH'ILA (Gk. a///;of, ammox, sand -- (I>i1nr, 7</ii7o.'!, friend, loving) . A genus of grasses, closely allied to Arundo. (See .) It is distinguished by a spike-like panicle, and by the character of the glumes, which are nearly equal, keeled, longer than the paleæ; of the single floret, and surrounded at the base by a tuft of hairs. Ammophila arenaria or Ammophila arundinacea, formerly called Arundo arenaria — a grass about two to three feet high, with rigid bluish leaves, the edges of which are rolled in, and creeping rootstocks — is frequent on sandy shores of Great Britain and the Continent of Europe. It is sometimes called beach grass, sea reed, or sand reed, and sometimes mat grass, because the culms are wrought into foot-mats, coverings for stairs, etc. It is also called marram, by which name it is designated in laws both English and Scottish, by which the destruction of it was prohibited under severe penalties, because of its great utility in fixing the shifting sand. In Holland and in Norfolk, as well as in the United States, it is extensively employed — along with the Sea lyme grass (q.v.) — in preserving the banks of sand which prevent the inroads of the sea. It is of little value as food for cattle, although they eat the very young leaves. The fibre has been used instead of flax, but is too short. Beach grass has been used in the manufacture of paper of coarse quality.

AM'MUNI'TION (Fr. amunition, probably by wrong division of la munition into l'amunition; from Lat. munire, to fortify, defend). A term which embraces all the ordnance stores used in the actual firing of guns of every sort and calibre, and which includes gunpowder, projectiles, primers, and their accessories. When the powder, projectile, and primer are so combined in a single piece as to be ready for firing as soon as placed in the gun, the packages so formed are called fixed ammunition; the term is also extended to ammunition for large guns in which the powder is inclosed in a primed metallic case, but loaded separately from the projectile. In small arms the ammunition is invariably of the fixed type. For heavy guns the ammunition is almost universally fixed for calibres of less than four inches. Above this, the practice is not uniform in all countries or in all classes of guns. In the United States Navy fixed ammunition is used in all calibres

FIXED AMMUNITION — UNITED STATES NAVY. 1. One-pounder. 2. Six-pounder, three inch and four inch. A. Brass Cartridge Case, bottle-necked at E. B. Rotating Band (copper). C. Projectile. D. Base of Cartridge Case. E. Bottle-neck of Cartridge Case. F. Primer.

of guns up to and including that of four inches; guns of five-inch calibre, of models antedating 1899, are also supplied with it; six-inch guns, except those of 1899 and later models, have the powder charge put up in primed brass cartridge cases, but the projectile is separately loaded. In other services, army and navy, the rule was, and is, about the same. In the new United States Navy guns (model of 1899), fixed ammunition is used for guns of four-inch calibre and less. No cartridge cases are used for the larger calibres. A new form of lock, which automatically ejects the primer, assists to make the loading with powder in bags quite as rapid as if it were incased in metal. The metallic cartridge cases used for fixed ammunition are now generally made of hard drawn brass of the best quality, stamped from sheets or plates of varying thickness, depending upon the calibre of the gun for which they are designed. The circular disk cut from the sheet or plate is first given the form of a shallow cup and then drawn out