AOATHIS 





sum** of CuMliu, Calcedony, Onyx, Sardonyx, Mocha-Stone, Blood- 

 stone, Chrnopnie, and Plaaua, are so donah- allied to agate, that 

 they mmy be conveniently described under thin howl In chemical 

 -it'ion they arc not di*tingishl n thu cam of the 



cnryaopnMv by lU colouring matter. Cornelian, HO called because 

 ome kind* are of a flih colour (carttit, Latin for flesh), U that variety 

 of a uniform colour which in of most common occurrence : carneliana 

 are never figured or striped. The colour* are abades of red and yellow, 

 the deep clear red being the rarest and must valuable. The great 

 upply uf carneliant ia from Japan, where they exist in vast quantities, 

 and they are abo imported from Bombay, being collected iu the 

 province of Ouxerat ; but the beat, according to Xicbuhr, com 

 the Gulf of Canibay. Many of the antique gems are engraved in 

 oamelian, and it is now much used for seals. Catcetlvny, so culled 

 from bavins been early found at Calchedou (sometimes incorrectly 

 written Chalcedon) in Bithynia, opposite Constantinople, is also of a 

 uniform colour, generally of a milky white or pale yellow, like turbid 

 jelly, often with an internal wavy structure in the form of stalactites, 

 and very generally with a peculiar mammillary surface. It is found 

 in great abundance in the Faroe Islands, in Iceland, in Cornwall, and 

 many places of Great Britain, as well as other countries ; BOH, 

 in large m*Bns, from which cups and other vessels are formed. Pliny 

 describes it as being found in the neighbourhood of Thebes in 

 and as brought to Home from Carthage. Chut is a kind of granular 

 calcedony, and forms a transition to the rock called Jlum 

 Onyx. In thu agate the silicious particles are arranged in altcmat i n ir 

 horizontal layers of opaque white and translucent blue, gray, or l>n n : 

 and because these have a resemblance to the marks on the human 

 noil, the stone was called from the Greek word for nail, JJKU(. It was 

 known to the ancients, and was employed by them, as it u now, fur 

 those beautiful gems called cameos, the figure being cut out of the 

 opaque white, the dark part forming the ground, or the contrary. It 

 is most valuable when the contrast of colours in strong, and when the 

 layer is thick enough to give a high relief to the object to be engraved. 

 In the royal library at Paris, there U an antique cameo cut out of on 

 onyx with four layers, representing the apotheosis of Augustus, eleven 

 inches by nine, which is supposed to be the finest in existence. Agates 

 with an onyx structure are not uncommon, particularly among calce- 

 donies, but the finest are brought from India. Cameos are sold at 

 Rome which are made from a thick shell, having different coloured 

 layers like an onyx. Sardonyx in a variety of onyx which is supposed 

 by some to have received iU name from having been brought from 

 skrdea, in Lydia. By others it has been said that the name comes 

 from Sardo, the Greek name of Sardinia, there being some reason for 

 thinking that the Carthaginians brought the stones from that island, 

 and exported them during their occupation of it. In this the opaque 

 white alternates with a rich deep orange brown of considerable trons- 

 luccncy, and as this is of rare occurrence the sardonyx ia of greater 

 value. The finest are brought from the east, and some antique gems 

 are formed of them. Mocha-Stona and ifou-Agata are semitran 

 calcedony, including various ramified forms, produced by iron, manga- 

 nese, bitumen, and chlorite or green earth, but sometimes also, as has 

 been proved by Daubenton and MacCulloch, produced by the presence 

 of real vegetable bodies, such as Confrrra and mosses. The first are 

 found in Guzerat, but received their name from having been brought 

 from Mocha, in Arabia. BlwHt-Htnn', or //it!nt,-n/>r, is a green agate 

 coloured by chlorite, with numerous bright red spots like drops 

 of blood. It is also called oriental jasper. Chrysoprate (from 

 Xfuaioi, golden or beautiful, and wpdvor, a leek) U a rare apple-green 

 calcedony, fonn.l in si!,--i ; . which OWCH its colour to the presence 

 of the metal nickel. Platma in another scarce green semitranspareut 

 calcedony, but of a dark tint, wliii-li, in tin- opinion of MacCulloch, in 

 coloured by chlorite. Sard is a deep reddish-brown variety. 



The great supply of the figured agates of commerce is from Ober- 

 dtein, in the old 1'nlatinate, about 30 miles east of Trevea, and 45 miles 

 south of Coblens. When they were used as buttons, knife-handle.', 

 he trade was more extensive than at present. They are found 

 in ninny parts of Scotland, especially at tin: Hill of Kinnonl, n..u- 

 Perth, where there is an amygdaloidal trap very full of fine Hpi 



A 'OATH IS is the generic name given by botanists to the trees, 

 known in common language by the name of Dammar ami KM'.-, i' 

 Pines. These plants belong to the natural order <'"iiiftr<i; from all 

 other specie* of which they are known, firstly, Kv their l>road, lance- 

 shaped, leathery leaves, the veins in which are numerous and nearly 

 parallel, diverging a little at the base, and converging at the apex ; 

 and, secondly, by their seeds having a wing on one side instead of 

 proceeding from the end. 



The Dammar Pine (Agathit loran-'hifiAia), or the Paint Dan, 

 of Linmeus,is a large tree found on the very summits of the mountain > 

 of A mboyna, Temate, and in many of the Molucca Islands. \Vh>-ii 



young it has something of the aspect of a young cedar, tin- n 1 ol 



which it U said to resemble. It is occasionally cultivated in the 

 hot-house* of curious persons; but is of little value except for it* 

 rain, which, when pure, is white, clear, ami brittle as glass, but in 

 time becomes amber-coloured. 



IU timber is represented to be light and of inferior quality, wholly 

 unfit for any situation exposed to wet, but answering tolerably well 

 for in-door purpose*. 



The Kawrii- Pine t.l.v'Au Atulralit) grow* only in New Zealand, in 

 the forats of which it attains a considerable height, with a straight 

 clean stem, which from it* lightues* and toughue**, ha* been found 

 well calculated for the uuutU of ships. It is diatinguiohed from the 

 Dammar Pine by it* narrower and more acute leaves, and by it 

 rapid mode of gi.mth. 



AOATHOI'HY 1.1. I'M ifr-iu Ityatin, good, and ^AAor, a leaf), a 

 genus of plants belonging to the natural order /xmnKttr, one ipecies 

 of which, ih. . I. iiromalicum, yield* the clove-nutmeg* of Madagascar. 



AGATlli i TKS ifroin ayaUmt, goodnen), a genus of plants belong- 

 ing to the natural order <,:,,:..i,..i.,.- It is distinguished by having a 

 rotate 4-parted corolla, w ith <.-.. |>ore* at the base of each m->. 

 A. chirayta is a well-known species, a native of Ncpaul, Kumium, and 

 the Himalayan. The specific name is an imitation of the Sanscrit and 

 Bengalee names. This plant has !><< n known for a great length of time 

 as a remedy in India. Imt him only recently U-en introduced into 

 European practice. It is an annual plant, about three feet high, 

 tlowerin:: in the rainy season. The whole plant is taken up, and the 

 proper time for collecting it w just when the flower* begin to . 

 \\ 'lieu dried it has an intensely but agreeable bitter taste, and is destitute 

 of aroma. The root is possessed of the greatest bitterness. The 

 Litter principle is readily imparted to water and to alcohol. [CUM 

 KM;. CYC., in Aim AMD Sc. Div.] 



AGA'VE, a genus of plants belonging to the natural m-der, 



IF. The species are known by the name of Am 

 Aloes, and produce clusters of long stiff fleshy leaves, collected in a 

 circle at the top of a very short stem, and bearing flowers in 

 terminal woody scape. With Duryantha and }'in-<- it forme in the 

 natural order Awaryllldacftt an instance of high development Imth in 

 vegetation and fructification, compared with what 

 characteristic of that tribe. If i: : an Amarylli* hail the 



stem elongated into a woody trunk, instead of living contrac-U'd 

 short disk, lying at the bottom of a scaly ImlK, the aitinity K. - 

 them and .I'/nn would at once be obvious. 



There are many species of this genus, one only of which requires to 

 be mentioned. 



Agare Americana, or the American Aloe, is a plant which, when full 

 grown, has a short cylindrical woody stem, which ia terminal 



American Aloe (Agate Americana). 



hard, fleshy, spiny, sharp-pointed, bluish green leaves, nK 

 long, and altogether resembling those of the arborescent aloes. 

 "f these leaves will continue to exist for m .-my yearn, so that but a 

 small numlier hnve withered away by the time tin plant has acquired 

 iU full maturity. It is commonly supposed that this occurs only at 

 i of one hundred yearn; but this, like many other popular 

 opinions, is on error; the period at which the Agave arrives at 

 maturity varying, according to circumstances, from ten to fifty, or 

 even seventy years. In hot or otherwise favourable climates, it grows 

 rapidly, and arrives sooner at the term of iU existence ; but in colder 

 regionc, or tinder the care of the ^gardener, where it is frequently 



