Epidote

“ The light [39] bluish green color of the fresh rock changes on exposure to a dull gray or yellow, and the massive ledges and slabs split up into thin schistose layers. It is quite compact in appearance, and as a rule very few macroscopic crystals can be seen in it.
A general separation can be made into an epidotic division characterized by an abundance of macroscopic epidote and a non-epidotic division with microscopic epidote. These divisions are accented by the general finer texture of the epidotic schist. ”

“ Its ready cleavage renders it liable to flaws; nevertheless, it is occasionally faceted. The name epidote, from ἐπίδοσις, increase, was given to it by Haüy, but not on very precise crystallographical grounds.
In composition this species is a silicate of calcium and aluminium, with some ferric oxide in place of alumina, corresponding to the complex formula, Ca2 (Al,Fe) 2 [ (Al,Fe) OH] (SiO4) 3. It occurs in monoclinic, prismatic crystals richly endowed with natural faces. The colour deepens with increase in the percentage amount of iron, and the stones become almost opaque. ”

“ In microscopic section they are often merely a granular mosaic of quartz and epidote with some iron oxides and chlorite, but in other cases they retain much of the structure of the original rock though there has been a complete replacement of the former minerals by new ones. Epidosites when streaked and variegated have been cut and polished as ornamental stones. They are translucent and hard, and hence serve for brooch stones, and the simpler kinds of jewelry. These rocks occasionally carry gold in visible yellow specks. ”

“ EPIDIORITE, in petrology, a typical member of a family of rocks consisting essentially of hornblende and felspar, often with epidote, garnet, sphene, biotite, or quartz, and having usually a foliated structure. The term is to some extent synonymous with “amphibolite” and “hornblende-schist.” These rocks are metamorphic, and though having a mineral constitution somewhat similar to that of diorite, they have been produced really from rocks of more basic character, such as diabase, dolerite and gabbro. ”

“ EPIDOTE, a mineral species consisting of basic calcium, aluminium and iron orthosilicate, Ca2 (AlOH) (Al, Fe) 2 (SiO4) 3, crystallizing in the monoclinic system. Well-developed crystals are of frequent occurrence: they are commonly prismatic in habit, the direction of elongation being perpendicular to the single plane of symmetry. ”

“ Biotite, if present, is brown; epidote is yellow or colourless; rutile, apatite and quartz all occur with some frequency. The essential minerals, hornblende and felspar, rarely show crystalline outlines, and this is generally true also of the others. The rocks may be fine grained, so that their constituents are hardly visible to the unaided eye; or may show crystals of hornblende an inch in length. Their prevalent colour is dark green and they weather with brown surfaces. In many parts of the world epidiorites and the quartz veins which sometimes occur in them have proved to be auriferous. ”

“ It is fresher; than most of the rocks in these hills, that is to say, it is less disposed to break into irregular fragments with decomposed surfaces. It sometimes contains veins of epidote, and in one instance I found in it a slender vein of calcareous spar. Subordinate portions of a mixture of hornblende and felspar occasionally occur in it, and sometimes the hornblende, felspar, quartz and mica are combined in equal proportions, forming a uniform mass. ”

“ Though occasionally we may find larger grains of felspar, quartz or epidote, it is more characteristic of these rocks that all the minerals are in small, nearly uniform, imperfectly shaped individuals. ”

“ It is not confined to the End-hill, but I found it in greater abundance there than in any other part of the range, particularly on the northern side of the valley, which separates that hill from the North-hill, and among the loose fragments that are scattered over that valley. It is very often found in veins mixed with quartz and with felspar, but the only place where I found it forming the constituent part of a rock was at the northern face of the End-hill. In some instances, the epidote would scarcely perhaps be recognized, especially where it is much mixed with felspar or quartz ”

“ In a part of the rock, which is almost inaccessible, there is a vein of Epidote, distinctly crystallized, and about six inches wide. The miners, however descend the fearful precipice without any difficulty, in order to collect specimens for the inquisitive visitant. Axinite also [136] occurs in veins, or perhaps in beds; Thallite, Chlorite, Tremolite, and a black crystallized Schorl, in which the late Rev. ”

“ In epidote it has been shown that the two directions 589 of maximum absorption which lie in the plane of symmetry are not even at right angles.
The pleochroism of some crystals is so strong that when they are viewed through in different directions they exhibit marked differences in colour. Thus a crystal of the mineral iolite (called also dichroite because of its strong pleochroism) will be seen to be dark blue, pale blue or pale yellow according to which of three perpendicular directions it is viewed. ”

“ Epidote, ep′i-dōt, n. a silicate of aluminium, iron, and calcium.
Epigastrium, ep-i-gas′tri-um, n. the part of the abdomen which chiefly corresponds to the situation of the stomach, extending from the sternum towards the navel.—adj. Epigas′tric. [Gr. epi, upon, gastēr, the stomach.]
Epigene, ep′i-jēn, adj. applied to the geological agents of change which affect chiefly the superficial position of the earth's crust, as the atmosphere, water, &c.—adjs. Epig′enous, growing on the surface of a part; Epigē′ous, growing on the earth—also Epigē′al. [Gr. epi, upon, gennaein, to produce.] ”

“ The irregular-shaped hornblende crystals show strong pleochroism, from pale olive-brown to moderately deep green. The extinction angles are large, being frequently over 20°. Twinning of the crystals is fairly common. Many of the crystals [317] are clouded, and the alteration of the mineral has resulted in the formation of much epidote. The plagioclase is only present in very small quantity, strongly clouded by decomposition, but still showing twinning clearly. The quartz is clear, and is likewise present in very small proportion, mostly interstitial. ”

“ These rocks are always very heavy and extremely tough; they weather commonly into great rusty-looking rounded blocks, and a sledge hammer is required to get a specimen.
Fig. 43.—Amphibolite, from hills near Gebel Um Gunud [11,511] , × 30. Almost the whole of the figure is occupied by hornblende, which is seen clouded and altering to granular epidote at e. Part of a large grain of calcite, bordered and streaked with iron oxide, is seen at c, while q is a small crystal of interstitial quartz. ”

“ Apatite, or mineral phosphate of lime, is found in [Pg 236] large deposits in different places. It is particularly abundant in Spain, and occurs also in America and Norway. From the latter country it has been imported to some extent; and during the last year considerable quantities have been brought from Spain, and the importations will undoubtedly increase very largely as the means of transport improve in that country. Spanish apatite contains—
Several other varieties of mineral phosphates have been imported under the name of guano. ”

“ Apatite occurs in hexagonal prisms, usually with the ends truncated by a basal plane, and with one or more sets of pyramidal faces between the prism and the basal plane. Crystals range in size from tiny to over a foot in diameter. There is but one cleavage and that is basal. The crystal 161 form, cleavage, and hardness will easily determine this mineral. Apatite is usually associated with igneous or highly metamorphic rocks, such as granites, gneisses, and crystalline limestones. ”

“ It was impossible that there should be no discharge of mucus from the nose, since man's body has been composed as it is; for that reason nature made hands, and the nostrils like tubes to discharge the humours. If, therefore, a man snuffs back these discharges of mucus, I say that he is not acting as a human being should. 10It was impossible that the feet should not get muddy, nor dirty at all, when they pass through certain such substances; for that reason nature has provided water, for that hands. It was impossible that some impurity from eating should not remain on the teeth ”

“ DETERMINATION OF PHOSPHORIC ANHYDRIDE IN APATITE The mineral apatite is composed of calcium phosphate, associated with calcium chloride, or fluoride. Specimens are easily obtainable which are nearly pure and leave on treatment with acid only a slight siliceous residue. ”

“ I prefer ipecac to tartar emetic, because the action of the former is more gentle and more constant, and because tartar emetic irritates the mucous membrane of the stomach. After ipecac, the patient remains calm, whilst after tartar emetic, the nausea continues, and is very often followed by diarrhœa. I insist strongly on patiently awaiting the effect of the ipecac before giving warm water, because prematurely swallowed, this embarrasses instead of promoting the effect of the medicine. ”

“ With regard to its mode of occurrence, apatite is found under a variety of conditions. In igneous rocks of all kinds it is invariably present in small amounts as minute acicular crystals, and was one of the first constituents of the rock to crystallize out from the magma. The extensive deposits of chlor-apatite near Kragerö and Bamle, near Brevik, in southern Norway, are in connexion with gabbro, the felspar of which has been altered, by emanations containing chlorine, to scapolite, and titanium minerals have been developed. ”

“ From 1500 to 3500 tons of apatite are obtained yearly in Norway from these veins. In Ontario apatite has been worked for a long time in deposits of similar nature. The total output of Canada in 1907 was only 680 tons.
The phosphatic rocks which occur among the sedimentary strata are the principal sources of phosphates for commerce and agriculture. They are found in formations of all ages from the Cambrian to those which are accumulating at the present day. ”

“ Phosphorite is another name for apatite, but is chiefly applied to impure amorphous apatite. The percentage of phosphate of lime in different kinds of apatite may be stated at from 70 to 90 per cent. It occurs in very large quantities in Canada, the Canadian apatite being very rich in phosphate of lime—80 to 90 per cent. In many parts of the world it forms portions of mountain-masses, and is quarried, crushed, and used for artificial manurial purposes. Further details of its occurrence and chemical composition will be found in the Appendix. [123]
Coprolites. ”

“ In the woody column they are obvious; the prevailing tissue consists of short pitted vessels. The cortical parenchyme and the medullary rays are loaded with small starch granules. Some cells of the interior part of the bark contain however only bundles of acicular crystals of oxalate of calcium.
Chemical Composition—The peculiar principles of ipecacuanha are Emetine and Ipecacuanhic Acid, together with a minute proportion of a fœtid volatile oil. The activity of the drug appears to be due solely to the alkaloid, which taken internally is a potent emetic. ”

“ In the adult the endopodite is a mere vestige, while the flat outgrowths from the protopodite have become very large and bear setæ.
Summary.
The limbs of most Crustacea are readily explained as modifications of a simple biramous type. These modifications usually take the form of reduction by the loss or fusion of segments and quite generally either the entire endopodite or exopodite is lacking. Modification by addition frequently occurs in the growth of epipodites, "endites," and "exites" from the coxopodite, basipodite, or both. ”

“ Dissolve a teaspoonful of salt in water and give to the patient, or administer a teaspoonful of ipecac every few minutes to a child, and a tablespoonful to an adult. Follow the dose with a glass of water and then insert the forefinger in the throat. One who has taken opium does not vomit easily and strenuous efforts should be made to produce vomiting. ”

“ It purges melancholy, and other humours, it strengthens the stomach and liver, cleanses the body of addust choler and addust blood, as also of salt humours, and helps diseases proceeding from these, as scabs, itch, tetters, ringworms, leprosy, &c. A man may take two ounces at a time, or add one ounce to the Decoction of Epithimum. ”

“ Black vomit often comes soon after the administration of an ill-judged emetic. The principle indication are these—the tongue humid, saburral, charged with whitish mucous deposits, nausea, disposition to vomit, bad taste in the mouth, the temperament bilious, constitution lymphatic, atmosphere damp, etc. Administered under these circumstances in the first period of the invasion, the emetic is a heroic remedy. I prescribe thirty grains of ipecac, dissolved in six ounces of distilled water, taken in one draught. ”

“ This singular creature has the appearance of an Eurypterus with the carapace of a Pterygotus. The Pterygotuslike aspect of the carapace is principally due to the marginal position of the compound eyes.
Another character worthy of mention is the ornamentation, [6] which consists of flat, imbricating scales that are crescentlike near the anterior margin and become angular posteriorly. They are evenly distributed over the entire body, carapace [pl. 60, figs. 6, 8] , endognathites, metastoma, operculum and its appendages, save the telson where they have not been observed. ”