several smaller "notes." A tolerably complete list of which may be found in Erdmann's Journal für praktische Chemie, i, 1. It is very much to be regretted that these memoirs have never been collected and published as a separate volume. Even now, any chemist who could find time to collect these scattered articles and translate them into English or French, would unquestionably promote the cause of science by so doing. Looking at the question for a moment, solely in its scientific bearings, we cannot refrain from an expression of astonishment, that the details of Reichenbach's researches are so little known to the generality of chemists; while, on the other hand, we are forced to confess, that it is indeed rare that scientific researches, conducted by a chemist in his laboratory, have so fully described a future art-have so accurately pointed out the methods to be followed and precautions to be observed by the practical manufacturer. We must not omit to mention that, in 1831, Christison of Edinburgh made known his discovery of paraffine in petroleum from Rangoon. Not knowing of Reichenbach's previ ous publication, Christison named it Petroline, but subsequently admitted its identity with paraffine. In 1833, Bley‡ distilled oils from lignite. A little later, in 1834, Gregory§ published an able article upon paraffine and eupion, and their occurrence in petroleum. Of this memoir we cite but two lines, (vid. Trans., p. 129, or Rep., p. 113). "It follows," says Gregory," that there are some kinds of naphtha [petroleum] which contain paraffine and eupion, and are consequently the results of destructive distillation." In the following year, v. Kobell|| also noticed paraffine in petroleum. For the labors of Hess in Russia, and of several other chemists in Germany, as well as for the interesting discussions which followed between these * This lack of information appears to depend upon the circumstance, that the writers of most recent chemical text-books seem to have derived their knowledge of the subject in question, from Gay Lussac's brief abstract of Reichenbach's earlier memoirs, which was published in 1832, in Poggendorff's Annalen, xxiv, 173; also in the Annales de Chimie et de Physique, [2], 1, 69; and quite extensively copied by the journals of the day. In this connection we would respectfully urge upon all those who have fallen into the common habit of regarding as somewhat apochryphal the numerous substances of greater or less scientific interest, which Reichenbach separated from the products of dry distillation, that before seeking to discredit-or allowing themselves to disbelieve-them, they should conduct experiments similar to his, on a scale of equal magnitude. Let us here also bear in mind the luminous conclusion of the late Dr. HOPE of Edinburgh, who, as the story goes, (Vid. London Chemical News, i, 56), one day informed his class that Reichenbach had discovered in tar," creosote, picamar, paraffine, cedriret, capnomor, and a host of other substances of no interest or importance whatever." Of these "unimportant" substances, two at least, eupion and paraffine, are to-day as well known, in the world, as bees wax or spermaceti, although comparatively little--we had almost said nothing--has been added to the scientific knowledge of them, since the publication of Reichenbach's memoirs. If, perchance, any other of these well-nigh forgotten bodies should be found to possess any technical importance, we would quickly enough find some one claiming credit for its "discovery," and oppressing chemical nomenclature, by adding yet another name to the existing "host." Even now we await, with no little interest, the elucidation of the question--whether the new violet dye, prepared by oxydizing anilin, which is exciting so much interest, under the names anilein, Perkin's purple, mauve, etc., is not identical with, or a component of, the pittical of Reichenbach. Transactions of Royal Society of Edinburgh, xiii, 118; also in Repertory of Patent Inventions, 1835, [N. S.] vol. iii, p. 390. Schweigger Seidel's Journal für Chemie u. Physik, B. lxix, [B. ix, of the NeuesJahrbuch], S. 129. § Transactions of Royal Society of Edinburgh, xiii, 124; also in Repertory of Patent Inventions 1835, [N. S.] vol. iv, p. 109. J. pr. Chem. v. 213. observers and Reichenbach, the reader may consult the general index [Namen-u. Sach-Register zu den Bänden i. bis lx, Leipzig, 1845] to Poggendorff's Annalen der Physik u. Chemie. At the same time that these scientific researches were in progress in Germany and Scotland, or even earlier, numerous practical efforts to manufacture oils from bituminous substances were made in France. Although the precise date at which these experiments were commenced is somewhat obscure, it will not be difficult to trace the history of the successful development of the industry to which they gave rise. As stated by Dr. Antisell, the MM. Chervan* had a patent, dated in 1824, for distilling bituminous substances. Blum and Moneuse, in 1832, claim only the application of coal-oil to purposes of lighting-not its manufacture, which they allude to as being well known. Subsequently (7th October, 1833) Boscary obtained a patent for extracting pyrogenous oil from different substances, asphaltums, etc., and especially from the shales which occur in the environs of Autun (Saone et Loire), and finally from all the bituininous matters in France. The oil, which is obtained by distilling the shale in metallic cylinders, may be used, according to Boscary, instead of fish-oil or resin, for gas-making-a much better gas than that prepared from coal being thus obtained. In 1833, Laurent occupied himself with the investigation of various bituminous shales, both French and English, at the instance of the MM. Blum, whom he mentions as being occupied with the distillation of oil from the shales of the environs of Autun. Laurent gives the details of the process employed by himself, telling us that the retort in which his shales were distilled attained a sombre red heat at the close of the operation; also of the percentage amounts of oil (20 p. c.), gas, coke and water obtained from the Autun shale; how the oil cannot be burned in ordinary lamps, on account of smoking, but affords a very luminous flame when consumed in lamps furnished with suitable chimneys. He shows moreover that the oil contains paraffine, and does not contain naphthaline. Laurent subsequently published another paper upon this oil, in which article he records his efforts to ascertain what definite chemical compounds are contained in the oil. One of the products obtained by fractional distillation, viz., an oil boiling at 167° to 170° (C.) = 333° to 338° F., he considers as identical with eupion. In 1834, we find, for the first time, an article** describing the process of Selligue, although it would appear from the statements of this chemist and of others, that his attention had been directed to the subject of distilling bituminous shales several years earlier. The cited article relates how the shale is slowly distilled in iron cylinders, until no more oil comes over; how the oil obtained is characterized by containing neither oxygen nor naphthaline, but a solid substance differing from the latter, and resembling that called paranaphthaline by Laurent * Brevets d'Invention xviii, 232. Ibid. lxviii, 359. Annales de Chimie et de Physique, liv, 392. + Ibid. lxv. 250. According to Laurent, he had himself proposed to a company, in 1829, to work these shales, in order to extract the oil contained in them, and to employ it for lighting. ¶ Comptes Rendus, 1837, iv, 909; more fully in Annales de Chimie et de Physique, lxiv, 321. **Journal des Connaissances Usuelles, Dec. 1834, p. 285; also in Dingler's Polytechnisches Journal, 1835, lvi, 40, from which our extract is taken. + The inadvertency of confounding this body with paraffine was subsequently corrected by Selligue. In 1834, '35 and '36, Selligue* was principally occupied with his well-known process for making water-gas. In calling the attention of the French Academy to this, he remarks that, in conjunction with David Blum, he holds a patent granted in 1832 for the application of oils obtained from shale to purposes of direct illumination, and that the working of the shale employed is in the hands of a company capable of developing the business to any extent which commerce or the arts may require. In the same year Payen,‡ in reporting upon Selligue's water-gas, remarks upon the great importance of the new industry of distilling oil from shales which S. has introduced. In the following year we again find Selligue before the Academy§ requesting that body to appoint a committee to examine the merits of his new system of gas-lighting; his process of distilling bituminous shales on the great scale by means of apparatus, each one of which furnishes from 1,000 to 1,400 pounds of crude oil per day-this being about 10 per cent of the weight of the shale employed, and being almost all which exists in the raw material; also of his process of separating various products from the crude oil, some of which are applicable to the production of gas, others to ordinary purposes of illumination, and others to different uses in the arts. This petition was referred to a committee of three-Thenard, D'Arcet and Dumas-who reported in 1840.|| They mention the localities of Selligue's three establishments for obtaining oil from shales; the amounts of oil obtained from the different kinds of shale, &c. In 1838 Selligue also obtained a new patent¶ " for the employment of mineral oils for lighting." In his specification he informs us that the principles upon which his processes for rendering the oil obtained from shales proper for the purposes of direct** illumination depend, are: I. Removal of almost all odor. II. Removal of all tar. III. Removal of the most volatile portions of the oil, which are also the most inflammable and the most odorous, the presence of which would cause the oil to have too great fluidity for the capillarity of ordinary wicks. * * * The operations, continues Selligue, consist in slowly distilling the bituminous shale, and collecting the liquid products in large receivers. These products are redistilled, and divided into fractions by refrigerating. They are treated with concentrated sulphuric acid for a longer or shorter time according to the nature of the shale employed. Twenty-four hours are ordinarily sufficient, the oil being agitated from time to time. The quantity of acid used varies from to z After this the oil is to be carefully drawn off from the tar, and washed with water. Slaked lime is then added and a current of steam passed through the oil in order to carry off by distillation all the more volatile and odorous liquids. This last, says Selligue, is the most important part of my process, for if this very inflammable portion were allowed to remain in the oil, one could not use the latter in ordinary lamps à courant d'air. * * This patent it should be observed claims only to be an improvement upon that of Blum and Moneuse (vid. Supra). Selligue asserts, however, that coal-oil had never before been prepared in such a manner that * * See seven patents in Brevets d'Invention, lxx, 269. Of these patents two are dated 1834; two, 1835; and three, 1836. For a description of his process of gasmaking see also Bulletin de la Société d'Encouragement, Oct. 1838, p. 396; or Dingler's Polytechnisches Journal, lxxi, 29. + Comptes Rendus, 1837, iv, 969. Dingler's Polytechnisches Journal, lxviii, 201; from Bulletin de la Société d'Encouragement, Dec. 1837, p. 493. § Comptes Rendus, 1838, vii, 897, Comptes Rendus, x, 861; also in Dingler's Polytechnisches Journal, lxxvii, 137. ** The term "direct illumination" is constantly used by Selligue in contradistinc tion to the indirect use of the oil in his process of gas-making. it was fit for use in common lamps. This has, indeed, he says, been the subject of inany researches, but no one has hitherto succeeded in avoiding the empyreumatic odor, and the very inflammable products which caused the oil to rise too quickly to the summit of the wick. He goes on to define the difference between his purified oil and the crude oil obtained directly from shale. On the 27th of March, 1839, Selligue specifies certain additions and improvements to the preceding patent. I should add, he says, that I now divide the products of distillation into four distinct parts, which afford ine every facility for employing these products in the arts and for domestic economy. In these divisions there are indeed some anomalies which arise from differences in the shales, &c. which I treat; but the following products are always obtained: * I. A light, volatile oil more or less odorous according to the source from which it is derived. This can be used in painting, for dissolving resins, &c., for lighting by vaporising it (it being very volatile) or for the production of gas according to my system. II. A fat oil only slightly volatile, and having but little odor; this can be used for domestic purposes in ordinary lamps with or without admixture of animal or vegetable oils. III. A fatty substance almost odorless, possessing all the properties of the fats, and well adapted for use in the arts. It can also be used for lighting, either by mixing it with light oils or by decomposing it for the production of gas. It can moreover be used for soap* since it saponifies very well, and being without odor affords a very good soap; with ammonia the fat forms a sort of pomade. IV. An odorless pitch of great purity and tenacity, suitable for preparing a black solid varnish for preserving wood, iron-work, &c. * In 1839, Selliguet in alluding to the use of his oils in the treatment of cutaneous diseases speaks of the three large establishments for the distillation of bituminous shale which he has erected in the Department Saone et Loire, and mentions the fact that the oil (crude ?) is furnished at the rate of about two cents [ten centimes] per pound. The question of price is again discussed a few years later, when Selliguet says it has been stated that crude shale oil costs only $150 per 100 pounds, and that it contains 60 per cent of a very light volatile ethereal oil well suited to afford light, as well as 40 per cent of a fat substance. Now since 1837, I have extracted more than 4,000,000 pounds of oil from bituminous shale, but the oil (crude?) costs 20 cents a gallon (22 frs. the hectolitre) or even 27 cents when delivered in Paris. From every hundred measures of the crude oil are obtained (by distillation) 20 measures of volatile oil boiling at 100° C. 212° F.; 30 measures of less volatile oil boiling at 150° to 260° C.=302° to 500° F.; 14 measures of an oil containing paraffine, and 28 measures of fat-five measures being lost. In purifying these products a further portion is lost. The clearest of all Selligue's specifications, however, is that of the patent granted to him March 19, 1845§ for the distillation of bituminous shales and sandstones. After describing the various forms of apparatus used in distilling, into one of which superheated steam was introduced, he enumerates the products of distillation as follows: I. A white, almost odorless, very limpid mineral oilsomewhat soluble in alcohol-which may be used as a solvent, or for purposes of illumination in suitable lamps, &c. *This "soap," (emulsion) is described more fully in the sequel. + Comptes Rendus, ix, 140; also Annalen der Pharmacie, von Wohler u. Liebig, xxxii, 123. Dingler's Polytechnisches Journal, xci, 193; from the Moniteur Industriel, 1843, No. 770. § Brevets Invention, [new series, (loi, du 5 Juillet, 1844,) ] iv, 30. II. A sparingly volatile mineral oil of sp. gr. 0.84 to 0.87, of a light lemon color, perfectly limpid, almost odorless, never becoming rancid, and susceptible of being burned in ordinary oil lamps, of constant level à reservoir superieur, with double current of air—a slight modification of the form of the chimney and burner being alone necessary. This oil can also be mixed with the animal or vegetable oils. Oils thus prepared do not readily become rancid, nor do they congeal easily when subjected to cold. III. A fat mineral oil, liquid at the same temperature as olive oil. This oil contains a little paraffine; it is peculiarly well adapted for lubricating machinery, and has an advantage over olive and other vegetable oils, or neatsfoot oil in that it preserves its unctuosity when in contact with metals and does not dry up. It saponifies easily, and forms several compounds with ammonia. IV. From the oils Nos, I, II, and III, I extract a red coloring matter which can be used in various arts. V. White crystalline paraffine which needs but little treatment in order to be fit for making candles; this substance does not occur in very large proportion in the crude oil, and the proportion varies according to the different mineral substances upon which I operate. There is but little of it in petroleum, and in the oil obtained from bituminous limestone. I often leave a great part of the paraffine in the fat oil and in the grease in order that these may be of superior quality. VI. Grease. This grease is superior to that of animals for lubricating machinery, and for many other purposes, since it does not become rancid, and remains unctuous when in contact with metals. VII. Perfectly black pitch-very "drying"-suitable for preserving wood, metals, &c. VIII. An alkaline soap obtained by treating the oils with alkalies. IX. Sulphate of ammonia. X. Manure prepared by mixing the ammoniacal liquor, or the blood of animals, with the crushed fixed residue (coke) of the shale. XI. Sulphate of alumina from the residue of the shale. [To be concluded.] F. H. S. SCIENTIFIC INTELLIGENCE. I. CHEMISTRY AND PHYSICS. 1. On Chlorophyll.-FRÉMY has communicated the results of an interesting investigation of the green coloring matter of plants. His conclusions are as follows: 1. Chlorophyll may be decomposed into a blue and into a yellow substance. 2. These substances give compounds with alumina which are insoluble in water. When hydrate of alumina is added to an alcoholic solution of chlorophyll, neither of the constituents of the latter unites with the earth. When, however, water is added gradually, the blue substance and a little of the yellow first unite with the alumina to form a dark green precipitate, while the alcoholic solution remains yellow. Both bodies are precipitated together from a very dilute aqueous solution. To separate the blue and yellow substances completely, the author introduces a mixture of two parts of ether, and one part of muriatic acid, diluted with a little water into a bottle, and shakes the whole till the muSECOND SERIES, VOL. XXX, No. 88.-JULY, 1860. |