transferred to the Mont Cenis, where it existed till 1827. Glass was made at St. Louis in 1790. In 1753 there were glass works at Marato, in Spain.

In the middle of the 16th century, A.D. 1553, the Germans appear to have already established glass works. Their products differed from the Italian and French, consisting principally of cylindrical tumblers or drinking-glasses called wiederkoms of transparent white glass decorated with coats of arms, devices, and mottoes painted in enamel on the outer surface in divers colours. The Germans also made schmelz glass. Later, battles and other subjects in grisaille were painted on their glass and produced by the makers, J. Schapper, of Nürnberg, in 1661-6; J. Keyll in 1675, and H. Benchert in 1677. Engraved glass was made at Prague, in Bohemia, by Caspar Lehmann in 1609, and continued by the Schwanhards at Nürnberg and Ratisbon in 1667-96. They engraved with the lapidary's wheel on crystalline glass, and are supposed to have discovered the art of engraving on glass by fluoric acid. H. Schwinger, a celebrated glass engraver at Nürnberg, died in 1683. Considerable prices were realised for these wares in the 18th century, some of the engraved glasses selling for as much as £150. At Potsdam there was a glass work, subsequently transferred to Rispen, about 1736. The director of this establishment, J. Kunckel, made ruby glass in 1679, with or without the use of gold. Glass was also manufactured and engraved in Holland before A.D. 1662. All these European countries have continued to make different kinds of glass.

In England, according to Bede, glass makers were introduced from Italy, about A.D. 674, for the purpose of glazing the church and monastery at Wearmouth. Small plates of glass for windows are mentioned by St. Jerome and Gregory of Tours in the two previous centuries. They were used in the Palace of Woodstock, in 1265. Glass was also extensively used for the painted windows of cathedrals and other edifices, and Edward I. had urinals of this material. In a charter of 1386, glass is mentioned, and foreign glass was sold in the port of London as above stated in 1389. The first mention of English-made glass is in a charter of A.D. 1447, in which J. Prudde agrees to glaze the windows of the Beauchamp Chapel at Warwick, without using English glass. It is mentioned in 1485, and more than half a century later, in 1557, at which

with a device or letters, the name or emblem of the host or tavern. Those of the Mitre Tavern had a mitre and W. P., the initials of the host. Some of them were of amber glass shaped like flasks, and covered round with wicker work. These continued till a later period, and one with the initials of Dean Swift was exhibited recently in Dublin. In 1673, the Duke of Buckingham introduced Venetian artists, who made mirrors and drinking-glasses at Lambeth. In 1688, Thevant, a Frenchman, invented the art of casting glass plates, but it did not come into use till a later period. In 1711, the British Plate Glass Manufacturers' Company was established at Ravenshead, near Prescott. Cookson made plate glass at S. Shields in 1728, and the Thames Plate Glass Company was established in 1835. Since then the principal advance made in the art in England has been due to the repeal of the duty on this material, and the production of coloured glass ornaments cheaper in cost if not superior in style to Bohemian glass.

In Scotland glass appears about the reign of James VI. It was subsequently made at Wemyss, Preston Pans, and Leith. In A.D. 1611 there were glass windows in the Palace of Holyrood. In 1840, patent plate glass was made. The rotatory process, as it was called, came into use in France in 1730, but not in Britain until 1832. Glass works were early established in America, at Temple, Newhaven, in 1740; at Jamestown, Va., in 1746; at Newhaven in 1789, and at Boston in 1809. They are since in activity at Boston, Baltimore, and New York. Prism glass was first made there.

(Pellat, Curiosities of Glass Making, 4to, Lond., 1849; Franks, Vitreous Art in the Art Treasures of the United Kingdom, 4to, Lond. 1858; Nesbitt, Catalogue of the Collection of Glass of Felix Slade, fol. Lond., 1871.)

GLASS-GALL, the saline scum on the surface of molten glass. It is also known as sel de verre, sel vitri, and sandiver. GLASS MANUFACTURE. [E. C. vol. iv. col. 390.] Many improvements have been introduced in the last ten or twelve years: some arising from new chemical combinations of ingredients, some from the use of improved apparatus. Mr. Chance, in a paper read before the Chemical Society in 1868, stated that France, Belgium, and America produce sand better suited for glass-making than any met with in England. The sand of Leighton Buzzard is now preferred among the English kinds, though not the whitest, because it contains least iron. A strong red sand, if containing no iron, may be whitened sufficiently by calcining with a little common salt. Welsh sand is found to produce striæ in the glass. Of the alkaline ingredient, carbonate of soda is still preferred for the best kinds of plate glass, but sulphate is often substituted on the ground of cheapness; for window glass the sulphate is found to be better than the carbonate. Powdered charcoal or anthracite facilitates the reduction of the sulphate, and promotes vitrification; as does also carbonate of lime; a little quicklime is added when sulphate is the alkali. For flint glass, oxide of lead is still the agent added to give lustre and rich refracting power. A little manganese is used to bleach sand tinged with iron for some kinds of glass. Mr. Chance gave the following as the chemical constituents of two old specimens of glass :

Fig. 14. English glass burette.

period J. Versaline, an Italian, manufactured glass at Crutched Friars. It was also made in the Savoy in 1567. Dollyne and Carey, of Antwerp, obtained a patent to make glass, and established themselves in London and Sussex; and G. Longe solicited for a new patent in 1589. In 1615, Sir R. Mansell obtained a monopoly of the importation of Venetian glass, and a patent for making glass with coal instead of wood. At this time Venetian glasses were kept in recesses along with silver plate as objects of rarity. About this time glass bottles of dark green glass for holding wine came into use, the oldest known being of the reign of Elizabeth. They were used in taverns, and stamped

Siemens' Regenerating Furnace [E. C. S. col. 1105] is now employed advantageously in glass-making. One of them, at Messrs. Chance's glass works, is 20 feet long, 10 wide, and 9 high; it is arranged for heating eight large melting-pots; economy is ensured by using slack instead of large coal, while the air in and around the furnace is kept in a purer state than under the old system.

Crown Glass is now almost a thing of the past. It is still made and used, but is being gradually superseded by

Sheet Glass. This useful kind, introduced into England by Messrs. Chance in 1832, and now largely manufactured by that firm, by Messrs. Hartley, and by other manufacturers, is in effect blown, like crown glass, but is treated in a different manner. [E. C. vol. iv. col. 396.] Of late years sheets have been obtained as large as 50 inches by 33. Sheet glass, however, often presents a rippled appearance, different from the undulating surface of crown glass, but, like it, unpleasant to the eye. To remove

By comparing the first and fourth in this list, or the fourth and eighth, or the fifth and seventh, enough will be seen to indicate that, had the measurements been proportional, the 14-inch tubes would have required only half the force per square inch to

crush them which the 7-inch tubes did.

Dr. Everett has published (Phil. Trans.' 1866, p. 185) an Account of Experiments on the Flexural and Torsional Rigidity of a glass rod, leading to the determination of the rigidity of glass; while in the volume for the following year, p. 139, the method is extended to rods of other materials, such as brass and steel. The method, which is highly ingenious, admits of minute deflections being measured. Cylindrical rods about 4 inch in diameter of flint glass, drawn brass and steel, were bent and twisted by known mechanical couples, so applied that the couple, whether of flexure or tension, was always uniform through the whole length of the rod. The amounts of bending and twisting thus produced in a given portion of the rod were measured by the aid of two mirrors clamped to the rod. In the earlier experiments these mirrors were made to reflect a dark line placed in front of a lamp-flame and the displacements of the images were measured on a screen. In the later experiments two telescopes were placed almost vertically over the two mirrors, so as to look down into them, and a sheet of paper, cross-ruled, was fixed in a horizontal position overhead. The displacements of the lines on this sheet, as seen in the telescopes, were then observed. From the measurements of flexure and tension thus obtained, the co-efficients of elasticity and rigidity for the substances operated on were calculated.

In the following table, M, n, and k denote the resistance, in kilogrammes per square millimetre, to linear extension, shearing, and cubical compression respectively, while o denotes the ratio of lateral contraction to longitudinal extension.

Steel. 21,793

8,341 18,756 •310

With respect to improvements in optical glass, we may refer to a notice by Professor Stokes, of the Researches of the late Rev. W. V. Harcourt-On the conditions of transparency in glass, and the connection between the chemical constitution and optical properties of different glasses,' published in the 'Report of the British Association' for 1871. Mr. Harcourt's researches extended over many years, and glasses were made of a large variety of materials. On account of the inconvenience of working with silicates, arising from the difficulty of fusion and the pasty character of the fused glasses, the experiments were carried on chiefly with phosphates, combined in many cases with fluorides, and sometimes with borates, tungstates, molybdates, or titanates. Many of the glasses, however valuable for optical purposes, are of a perishable nature or apt to tarnish; but it was found that disks of terborate of lead and of a titanic glass formed a fairly homogeneous combination, with which it is intended "to attempt the construction of an actual objective which shall give images free from secondary colour, or nearly so." So also the attention bestowed in the preparation and cutting of the various glasses "has been attended with such good results that now it was quite the exception for a prism not to show the more conspicuous dark lines."

GLASS-PAPER, like emery paper and sand paper, is used for smoothing dry substances by friction; small, sharp, hard par

ticles being glued or cemented down upon sheets of paper. The three kinds differ more in the nature of the particles than in the mode of making or using. [EMERY; EMERY PAPER, E. C. vol. iii. col. 857; SAND; SAND PAPER, É. C. vol. vii. col. 258.]

GLAZED WARE. [EARTHENWARE, E. C. vol. iii. col. 724; POTTERY, E. C. vol. vi. col. 676; POTTERY AND PORCELAIN, MANUFACTURE OF, E. C. vol. vi. col. 689.] Messrs. Minton have introduced the plan of converting parian into glazed ware, when required for baskets, centre-pieces, and diversified ornaments, as a means of enabling such articles to be easily cleaned; beautiful specimens of this kind were shown at the London International Exhibition in 1871.

GLAZER, or GLAZING-WHEEL, is a small, rapidly rotating wheel, presenting a surface suitable for polishing steel and other substances. [CUTLERY, E. C. vol. iii. col. 363; GLAZING (Metal Glazing) E. C. vol. iv. col. 405; LAPIDARY WORK, E. C. vol. v. col. 110; FACETTING, E. C. S. col. 951.]

GLEET, a colourless discharge from the urethra, often the sequel of gonorrhea, but sometimes due to other causes. of the eye), in anatomy, a name given to parts having shallow GLENOID, GLENOIDES (from yλhn, a cavity, the socket cavities, such as the socket of the shoulder joint, to a fissure and to a hole in the temporal bone, &c.

GLISSON'S CAPSULE, in Anatomy, the name of the vasattaches itself to them as they enter the transverse fissure, and cular membrane that surrounds the vessels of the liver, and are distributed through the organ.

GLOBULES, RED (dim. of globus, a ball), the disc-shaped microscopic bodies which are found in the blood of animals in large quantity, as the cause of its colour. [BLOOD, E. C., Nat. Hist. Div. vol. i. col. 509.]

GLOBUS HYSTERICUS, one of the strange sensations that occur in fits of hysteria. A ball seems to rise to the stomach, of that part. It is in part caused by flatus, and is often attended and thence to the throat, creating a feeling of extreme distension by frequent and noisy expulsions of wind.

GLORIA IN EXCELSIS, or supremis, in its Greek form, Aga e ioros, known, to distinguish it from the Gloria Patri, as the Greater Doxology, and as the Angelical Hymn, from the fact that its first part formed the choral ascription of praise with which a "multitude of the heavenly host" supplemented the announcement to the shepherds of the birth of Christ at Bethlehem. The Angelical Hymn belonged, until its appropriation by the Church universal, by right of production to the Greek section of the same, and was reckoned by the members of that communion as a morning hymn, having for its counterpart a shorter evening hymn, commencing

φῶς ἱλαρὸν ἁγίας δόξης.

The latter portion of this celebrated doxology, which is believed to be the earliest hymn extant, has been variously and inconclusively referred to Telesphorus, by birth a Greek, who, about the middle of the second century, was Bishop of Rome; to Hilary, Bishop of Poitiers, A.D. 350-368, the probable author of the Latin version; and to Symmachus, Bishop of Rome, about A.D. 500, who enjoined its use on all Sundays and holidays, except Advent, the Feast of the Innocents, and the season of Lent. In a very ancient liturgy of the Western Church, supposed to be as old as the seventh century, the hymn Gloria in Excelsis is found in a position which the English liturgy assigns to it, namely, amongst the thanksgivings after Communion, when it was an early custom of the Church to use a psalm, anthem, or hymn, in imitation of the Lord's example, who, after the Supper in which He instituted the Sacrament, sang a hymn with His disciples. In the Eastern Church this hymn is more than fifteen hundred years old; and the Church of England has used it, either at the beginning or the end of the liturgy, for over twelve hundred years. So late as the time of the issue of the First Prayer Book of King Edward VI. it was placed near the beginning of the Communion service, from which it was afterwards transposed. (Moroni's Dizionario Ecclesiastico; Riddle's Manual of Christian Antiquities; Palmer's Origines Liturgicæ : or, Antiquities of the English Ritual; and others.)

GLORIA PATRI, or the Lesser Doxology, as it is sometimes called to distinguish it from the Greater Doxology, Gloria in Excelsis, is a liturgical ascription of praise, the terms of which were very early dictated by the baptismal formula, "In the name of the Father, and of the Son, and of the Holy Ghost." The Gloria Patri, which is one of the earliest Christian examples of the tendency of mankind to mingle expressions of devout

blessing and honour with the words of prayer and supplication, was at first a single sentence without a response; and in this form an apostolic origin was claimed for it by St. Basil, who believed this kind of doxology to have been one of the ordinances or traditions, ràs Tapadóreis, the keeping of which by the Corinthians met the approval of St. Paul (1 Corinthians, xi. 2), who also exhorted the Thessalonians to observe the same (2 Thessalonians, ii. 15). Whether this be so or not, the antiquity of the Gloria Patri is understated when it is referred, as some have referred it, to the Council of Nicæa, the more probable merit of which assembly is that of fixing it in its present form, and of appending the clause "As it was in the beginning," &c., both the form and the added clause being conceived in opposition to the Arians, who held that the Father had begotten the Son in time, and that there had consequently been a time when the Son was not. The Arians had taken advantage of the various readings which before their rise had been allowed as harmless, and had pressed one of these, "Glory be to the Father, by the Son, in the Holy Ghost," to be the shibboleth of their heresy. Thus the orthodox fathers of the Council of Nicæa, by limiting the Gloria Patri to its existing form, are said to have imposed upon a hymn of praise the further significance of a shorter creed. In its second canon the Council of Narbonne (A.D. 589) decreed the chanting of the Gloria Patri at the close of each Psalm, and after each division of the longer Psalms; and the canon was so generally honoured by the Church, that Pope Alexander II. (A.D. 1061-1074) cited its universality as a reason why a special commemoration of the Trinity was not necessary to the perpetuation of the orthodox belief. One of this Pope's Decretals, which is sometimes erroneously attributed to Alexander III. (1159-1181), testifies that "the Festival of the Most Holy Trinity, with varying customs in various places, was by some persons observed on the octave of Pentecost, and by others on the Sunday next before the Advent of our Lord. The Roman Church did not observe it at any special time in this manner, because day by day the Gloria Patri was chanted, and other like things pertaining to the praise of the Trinity." The hymn is, further, of frequent occurrence in various liturgies, and is used in the formularies of different Churches at the close of most of the solemn offices.

GLOSSITIS, GLOTTITIS (yλŵtra, the tongue), inflammation of the tongue, a condition present in severe salivation, and as the result of the application of hot and acrid matters, but sometimes arising as an idiopathic affection. The inflammation may be treated by ice and iced water, but it sometimes requires to be relieved by free incisions.

10

GLUCOSAN, CHO, (C12H001). When dextroglucose, previously dried at 110°, is heated for some time to 170°, it gives off water and becomes converted into glucosan, contaminated, however, with small quantities of caramel and unaltered glucose. The former is removable by treatment with charcoal, and the latter by fermentation with yeast. Glucosan forms a colourless mass, having scarcely any sweet taste. It does not ferment in contact with yeast, but is reconverted into glucose by treatment with dilute acids. When heated with acids and alcohol, compound ethers are obtained related to glucosan in the same manner as the manitanides are to manitan. (Gélis, Compt. Rend. li. 331; Berthelot, Ann. Chim. Phys. [3] lxx. 96.)

GLUCOSE, CH12O6 (C12H12012). [GRAPE SUGAR, E. C. vol. vii. col. 883.] This is a species of sugar which is found in honey and in the juice of certain plants. It is also produced by the action of dilute acids on cane sugar, starch, dextrine, &c. There are two varieties of it distinguished by their action on polarized light, namely, dextroglucose, which turns the plane of polarization to the right, and lavoglucose, which turns it to the left.

DEXTROGLUCOSE, being crystalline, is easily separated from the uncrystallizable lævoglucose, and may readily be obtained pure by repeated crystallization from its aqueous solution. It then forms opaque white granular masses composed of the hydrate CH120+aq. It crystallizes, however, from dry alcohol in microscopic needles, which are anhydrous, and melt at 140°. It is much less soluble in water than cane sugar, and its taste is much less sweet. As above noticed, it turns the plane of polarization to the right.

LEVOGLUCOSE is isomeric with dextroglucose, and invariably accompanies it. When cane sugar is heated with water or with dilute acids, it is resolved into dextro- and lævoglucose, and at the same time loses its dextrorotary power, and acquires a lævorotary one: this is owing to the specific rotary power of levoglucose being greater than that of dextroglucose.

ARTS AND SCI. DIV.-SUP.

On treating with calcic hydrate the solution of inverted sugar, prepared by the action of dilute acids on cane sugar, a calcic compound of lævoglucose is formed which is solid, so that it may be readily separated from the corresponding soluble compound of dextroglucose. On decomposing the former by oxalic acid, lævoglucose is liberated. This is a colourless, uncrystallizable syrup, which dries up to an amorphous mass. It is much sweeter and more soluble in alcohol than dextroglucose. GLUCOSIDES, a term applied to certain vegetable principles which, when heated with dilute acids, decompose, yielding glucose or some other saccharine substance, and also a product peculiar to each individual glucoside. We must refer our readers to Gmelin's Handbook,' xv. 341, or Watts's 'Dict. Chem.' ii. 865, for a list of the sixty or seventy glucosides at present known. The most important of them, however, will be found described in articles in this Cyclopædia and Supplement. GLUE. [GELATINE AND GLUE, E. C. vol. iv. col. 327.] M. Wiedenbusch has recently been engaged on experiments having for their object to obtain a better test for the strength and adhesiveness of glue than those which are usually adopted. It has generally been supposed that the gelatinous element in glue is the only source of its strength, and that the market value can at once be determined if the proportion or percentage of gelatine is ascertained. Various agents-alcohol, tannin, sulphate of soda, sulphate of lime, and metallic solutions -are employed for this determination. M. Wiedenbusch is, however, of opinion that the tenacity of glue depends on other causes besides the proportion of gelatine it contains. He has described, in Dingler's Polytechnisches Journal,' a more elaborate test, applied through the medium of apparatus constructed by Desaya of Heidelberg. Small sticks of fine plaster of Paris are made, exactly alike in size, shape, and strength; they are dried, and kept in a stoppered bottle till required for use. When glue is to be tested, it is melted, and a plaster stick thoroughly saturated with it. A small mechanical apparatus is then set to work to break the sticks at a measured spot, and in a prescribed way. If a dozen or any other number of sticks, saturated with an equal number of different specimens of glue, are broken in this way, the mechanical force expended in effecting the breakage will measure the adhesiveness or strength of the glue, without any attempt to determine the per-centage of gelatine.

GLUTEUS (λovrós, the buttock), in anatomy, the name given to three muscles of the hip which form the bulk of the buttock. The vessels and nerves of this part are called glutaal.

GLUTAMIC ACID, CH,NO (2HO, CH,NO), is formed along with tyrosin and leucine by boiling wheat gluten with dilute sulphuric acid. It dissolves in about one hundred parts of water at 15°, and is much less soluble in alcohol. From its aqueous solution, which has a strongly acid reaction, it separates in anhydrous crystalline crusts composed of shining laminæ. It melts at 135° to 140° with partial decomposition, and forms a crystalline copper salt. Glutaric acid, CH ̧Ó (2H, C1H ̧ ̧), is formed by the action of nitrous acid on a solution of glutamic acid in nitric acid. It is very soluble in water, and crystallizes with difficulty. (Ritthausen, Jour. Pr. Chem. xcix. 454; ciii. 239; cvii. 218; and Zeits. Chem. [2] iv. 529.)

101

GLUTARIC ACID. [GLUTAMIC ACID, E. C. S.] GLUTEN-BREAD, a bread made of gluten, with the admixture of a certain quantity of starch. It is prescribed as an article of diet in Diabetes mellitus.

GLYCERALS. Compounds analogous to the Acetals, produced by heating glycerin with aldehydes to about 200° for 24 hours, acetoglyceral, valeroglyceral, and benzoglyceral, have been obtained. (Harnitz-Harnitzky and Menschutkin, Bull. Soc. Chim. [2] iii. 253.)

CH,Ho

GLYCERIC ACID, C,H,O,CHHO (3HO,C,H2O2)

When digested at 100° with concentrated hydriodic acid it is СМЕНІ converted into iodopropionic acid, and by the action COHO' of phosphoric chloride into chloropropionic acid. (Barth, Ann. Chem. Pharm. cxxiv. 341; Moldenhauer, do. cxxxi. 223; Wichelhaus, do. cxxxv. 248.)

=

CH,Ho GLYCERIN, C ̧ ̧ ̧ CHHO (CH,O,,3HO) [E. C. CH,Ho vol. iv. col. 411]. Glycerin is a trihydric alcohol, that is, contains three semimolecules of hydroxyl united with three different carbon atoms; only one other alcohol of this class is at present known, namely, amylglycerin. As glycerin contains three of hydroxyl, it is evident that by replacing one, two, or three of these by a halogen, such as chlorine, we may obtain three different ethers. The first of these, monochlorhydrin, C,H,C10,= CH,CI CHHO [E. C. vol. iv. col. 414], is found to be identical with CH,Ho

monochlorinated propylic glycol,

verted into propylic glycol,

and is con

=

SC(CH,C1) HHO }CH,Hồ CMeHHo CHH (CHO,,2HO), by the action of sodium amalgam. Dichlorhydrin, CH ̧CO2 CH,CI CHIO, the second of these, in which two of the hydroxyl are (CH,CI replaced by chlorine, is probably the same as dichlorinated isopropylic alcohol, C(CH2Cl)HHO (CH,C,O,HO), since it is converted into isopropylic alcohol by the action of sodium (CH,Cl amalgam. Trichlorhydrin, C,H ̧Cl ̧ CHCI, is the third CH,CI

CHCI

=

=

haloid ether, in which all the hydroxyl is replaced by the halogen. A fourth class of ethers also exists, closely related to these. The chlorinated one is formed by replacing two of the chlorine in trichlorhydrin by oxygen, thus forming epichlorhy(CH,CI drin, or glycerylic oxychloride, CH ̧CIO CH 0 EpiCH2 chlorhydrin, or monochlorhydroglycide, is prepared by treating dichlorhydrin with hydrochloric acid gas, or better, by the action of potassic hydrate on the same compound. It is a mobile liquid boiling at 119°, and is nearly insoluble in water. Of the corresponding bromine and iodine compounds which have been prepared, tribromhydrin has been proved by Henry to be identical with Wurtz's allylic tribromide. (Lourenço, Compt. Rend. lii. 1043; Buff, Bull. Soc. Chim. [2] x. 123; Reboul, Ann. Chim. Phys. [3] lx. 5; Henry, Deut. Chem. Ges. ber. iii. 298 and 601.)

GLYCERINE. Besides the useful purposes in the arts noticed under GLYCERINE [E. C. vol. iv. col. 412], glycerine is now made available in numerous ways. It is used instead of water to soften modeller's clay; to maintain collodion plates in a proper state of moisture for photographic purposes during several days; as an external application in affections of the skin and the ear; and internally as a solvent of many medicines.

Puscher, a German chemist, has found that when gelatine is mixed with one-fourth its weight of glycerine, it loses its brittleness, and becomes useful for many additional purposesin bookbinding, in leather-dressing, and in giving elasticity to various substances; when dry, the mixture has many of the properties of india-rubber. Mr. Haselden described to the Pharmaceutical Society, in 1866, a mode of combining these two substances for capsuling bottles and phials. Gelatine being too brittle by itself, glycerine is added, in the proportion of 1 oz. of the latter to 1 lb. of the former, melted with a very little water. When the mixture is melted, it is applied to the corked bottles in the same way as wax, the bottles being dipped several times until the thickness is sufficient. It will hermetically seal the bottle, whether the cork is driven down flush Many advantages attach to this mode of capsuling. The mixture being transparent, a name or trade-mark might be branded or printed on the top of the cork, and rendered visible through the capsule. Bitter aloes might be added to the melted mixture, for capsules which are likely to be attractive to insects in hot climates; while other ingredients might be used as safeguards against other attacks. Different colouring substances being introduced, the capsules might be made a sort of index to bottles containing different liquids.

or not.

GLYCERYL, C,H," (CH), the triatomic radical of glycerin and the glycerylic compounds. [GLYCERIN, E. C. S.] GLYCERYLIC HYDRATES. Besides glycerin, which is the normal hydrate, three others are known. They are derived from glycerin by elimination of the elements of water, in the same manner that the polyethylenic hydrates are formed from ethylic glycol. They are called diglycerin, (CH),H,O, (CH010); diglycide, (CH),H2O (C12H1208); and triglycerin, (CH),H,O, (CH20014), respectively.

14

GLYCERYLIC OXYCHLORIDE. [GLYCERIN, E. C. S.] GLYCERYLIC SULPHYDRATES, Thioglycerins. These compounds are produced by the action of potassic sulphydrate on mono-, di-, and trichlorhydrins, and may be regarded as glycerin in which the oxygen is partly or wholly replaced by sulphur. Monothioglycerin, CH,SO, (CH2SO), dithioglycerin, С‚Í‚§„O (CH,SO), and trithioglycerin, CH,S (CHS), are all syrupy liquids, readily soluble in alcohol, sparingly soluble in water, and insoluble in ether. (Carius, Ann. Chem. Pharm. cxxii. 72, cxxiv. 222.)

GLYCIDIC ETHERS. A class of dihydric ethers closely related to the glycerylic ethers, and formed from them by the action of alkalis. The most important are epichlorhydrin [GLYCERIN, E. C. S], epibromhydrin, and epiiodhydrin. GLYCOCINAMIDE. [GLYCOLLIC ACID, E. C. S.] GLYCOCINE. [GLYCOCOLL, E. C. S.]

GLYCOCOLL, Glycocine, amidoglycollic acid, Glycollamic acid, = {CH2(NH) CH,NO2 COHO or NH [CH,(COHo)] (HO,C,H,NO). [E. C. vol. iv. col. 415.] This acid is formed by the action of ammonia on chloracetic acid or bromacetic acid.

and also by heating uric acid with strong hydriodic acid to 170°. On heating ethylic chloracetate with ammonia, ethylic glycollamate (CNH) is produced, whilst chloracetic acid and ethylamine, on the contrary, yield ethylglycollamic acid, or SCH (NETH) When pure, ethylglycocine crysethylglycocine tallizes from alcohol in indistinct lamina, which have a sweetish taste, and melt at about 160° with partial decomposition. Like glycocine it forms compounds with metals, with acids, and with salts. Corresponding methyl and phenyl compounds have also been obtained.

The action of ammonia on chloracetic acid produces not only glycocine or amidoglycollic acid, but also amidodiglycollic acid, CH,NO1 =NH[CH2(COHO)], (2HO,CH,NO), and amidotriglycollic acid, CH ̧ÑO = N[CH,(COHo)], (3H0,C,,H ̧NO,). They are both crystalline solids, less soluble in water than glycocine, and insoluble in alcohol or ether. (Heintz, Ann. Chem. Pharm. cxxix. 27, cxxxii. 1, cxli. 355, cxxii. 127, and cxxiv. 297.)

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GLYCOCOLLAMIDE. [GLYCOLLIC ACID, E. C. S.] GLYCOCYAMIDINE. GLYCOCYAMINE, E. C. S.] GLYCOCYAMINE, C,H,N,O, (CH,N ̧0). When a solution containing cyanamide, CNH (CNH), and glycocine, C,H,NO, (CH.NO), is left to itself for a few days, the two unite, and colourless crystals of glycocyamine are formed. This compound, which is homologous with creatine, is insoluble in alcohol, only sparingly soluble in cold, but more readily in hot water. The hydrochlorate, C,H,N,Ó,Cl (CH,N,O,,HC), crystallises in rhomboidal prisms, and when heated to 160° loses water and becomes converted into glycocyamidine hydrochlorate, C ̧H ̧N ̧OCI (CHN ̧0,,HC). Glycocyamidine, C,H ̧Ñ ̧0 (СH ̧Ñ ̧1⁄2), is homologous with creatinine, and bears the same relation to glycocyamine that creatinine does to creatine. It is easily soluble in water, and forms a crystalline double salt with platinic tetrachloride. (Strecker, Compt. Rend. lii. 1212.)

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GLYCOGEN, Animal starch, Animal dextrin, hepatin, CH100, (C12H10010). This substance is isomeric with starch, and occurs in the liver and placenta of animals, in the muscles of the embryo, and in mollusca. It is a white, mealy powder, neutral, inodorous, and having a taste like that of starch. It is insoluble in alcohol, but forms an opalescent solution with water. boiling with acids, it is first converted into a substance cor

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