The canal now projected will unite the Don and the Volga, the first of these falling into the sea of Azof, and the second into the Caspian, near Astrachan, at a point designated on the maps as Tzaritsin. The two rivers are separated by a distance of only 55 kilometers. The importance of a canal which will connect the Caspian with the Mediterranean will readily be seen, and it must at the same time be confessed that it will be much more easily executed than the tunnel under the channel proposed by Mr. Thornè de Gamond, since the canal, being exclusively on Russian soil, will be a question for engineers, with which politicians will have no concern. For the last thirty years, it has been proposed to make a sea-port of Paris by a ship-canal leading from the Channel; the introduction of railways caused the project to be for a time abandoned, but it is now again discussed. Among the plans proposed is one which appears in the Ann. des Sciences of the 8th October, 1859. It is intended to excavate at the mouth of the Seine, near Havre, a harbor 1000 meters long and 200 wide, with a depth of 12 meters. The canal, 150 kilometers in length, will follow the course of the Seine, and will have the same depth as the harbor, which will be furnished with gates to preserve the water at a proper height. A double line of railway will accompany the canal, one line serving for passengers and freight, and the other for towing vessels, which will thus make the voyage in four hours. The position and direction of the canal will be such that the west winds, which are the most frequent at Paris, will help vessels in coming up, while the water of the Seine, to be let in by sluices, will aid them, by their current, in descending. The great difficulty in this enterprise will arise from the tunnels required, the total length of which will be from twenty to twenty-five kilometers. These will be vaulted, and with a height of 30 meters by at least 50 meters in breadth. Mr. Piorry estimates that the expense of this work may amount to a billion (1,000,000,000) of francs. Engineers are also occupied with a plan for joining the English Channel with the Mediterranean, by taking advantage of the river Rhone, the Saône, the Yonne, and the Seine. The details of its execution having only a local interest, we spare our readers their recital. SCIENTIFIC INTELLIGENCE. I. CHEMISTRY AND PHYSICS. 1. On two new series of Organic Acids.-HENTZ has studied the action of methylate of soda and similar substances upon chloracetic acid, and has obtained interesting new acids in which hydrogen may be considered as replaced by the deutoxyds of methyl, ethyl, etc. The acid resulting from the action of methylate of soda on chloracetic acid has the formula C6H6O6, which is that of lactic and paralactic acids, but is not identical with either of these. To this acid the author gives the name of methoxacetic acid; it is monobasic, and gives beautifully crystallized salts. The acid itself is easily prepared by decomposing the zinc salt with sulphu retted hydrogen, and distilling the liquid after separating the sulphid of zinc. The boiling point rises gradually till it becomes constant at 198° C., when the acid passes over as a colorless liquid, with a sour smell, resembling that of acetic acid. When monochloracetate of soda is boiled continuously, an acid liquid passes over, which, when saturated with baryta, yields on evaporation a crystallizable salt having the formula of glycolate of baryta. The author proposes for the acid contained in this salt the name of oxacetic acid; it is isomeric, but not identical with the glycolic acid. Its formula is C.H.O6. Ethylate of soda acts violently on monochloracetic acid; the products of the reaction are chlorid of sodium, and the soda salt of a new organic acid, homologous with the two last described, and which the author terms ethoxacetic acid. This acid is volatile without decomposition and appears to boil at a lower temperature than the corresponding methyl compound. Its formula is C8H8O6. Amylate of soda acts in a similar manner on monochloracetic acid. The new acid formed in the reaction is an oily liquid which has the formula C14H1406. Phenylate of soda, under similar circumstances, yields phenoxacetic acid, as an oily liquid which crystallizes at a low temperature, and distils over without decomposition. The analyses appeared, however, to show that the phenyl alcohol employed contained benzalcohol, and that the product examined was therefore a mixture of the homologous acids C16H8O6 and C18H1006. When the soda salts of organic acids are heated with monochloracetic acid, chlorid of sodium is formed, and new organic bodies which the author proposes to study. It is easy to see that all the acids belonging to the formic series will yield similar new acids with the peroxyds of the alcohol radicals homologous with hydrogen, and that in this manner a very great number of new compounds may be obtained.-Journal für prakt. Chemie, 78, p. 174. Note.-According to Kolbe's view, lactic acid is to be regarded as propionic acid, in which one equivalent of hydrogen is replaced by one of HO1, so that its rational formula is CoH (HO)002. O2. Upon this view the oxacetic acid of Heintz must be identical with glycolic acid, which appears not to be the case. The question may doubtless be decided directly by examining the products of the action of water upon chloropropionic acid, which ought thus to yield lactic acid directly, since we should have the reaction C6H4CIO5HO+HO2H=C6H4(HO2)O5HO+HCl. Heintz's acids may be more simply regarded as derived from the formic series by simple replacement of hydrogen by the peroxyds HO2,C2H3O2, C4H3O2, &c. Dichloracetic and trichloracetic acids ought to yield analogous products in which two or three equivalents of hydrogen are replaced by two or three equivalents of peroxyds which need not be of the same radical. The number of possible acids would thus almost or quite equal that of the ammonias or ammoniums. SECOND SERIES, VOL. XXIX, No. 66.—MARCH, 1860 W. G. 2. On the chemical constitution of Isethionic acid and Taurin.-By the distillation of isethionate of potash with perchlorid of phosphorus, Kolbe has obtained a new acid which has the empirical formula C4H6CIS2O5, and which he terms chlorethyl-sulphuric acid. This acid yields taurin by the substitution of NH2 for Cl, and ethyl-sulphuric acid C4H6S2O6 when the chlorine is simply replaced by hydrogen. Kolbe draws a parallel between the derivatives of carbonic and sulphuric acids, which is best illustrated by the following tabular view; C202.02 Carbonic acid. HO. (C4H4(HO2)),(C2O2),O Oxethyl-carbonic acid Lactic acid. S204.02 Amido-ethyl-sulphuric acid. HO. (C4H4(HO2))S204, O Oxethyl-sulphuric acid. The author promises a more detailed account of the compounds and reactions referred to in the above brief preliminary notice. Ann. der Chemie und Pharm., cxii, 241. 3. Researches on the atomic weight of Graphite.-BRODIE has communicated an exceedingly interesting and suggestive memoir on the atomic weight of graphite, considered as an allotropic form of carbon, the fundamental idea being that the different modifications of the same substance may exhibit a difference in equivalents, as well as in their ordinary chemical and physical properties. The author finds that graphite, when heated with nitric acid and chlorate of potash, increases in weight, and ultimately yields a light yellow crystalline substance. The details of the process are as follows: a portion of graphite is intimately mixed with three times its weight of chlorate of potash, and the mixture placed in a retort. A sufficient quantity of the strongest fuming nitric acid is added to render the whole fluid. The retort is placed in a water-bath, and kept for three or four days at a temperature of 60° C. until yellow vapors cease to be evolved. The substance is then thrown into a large quantity of water and washed by decantation nearly free from acid and salts. It is then dried in a water-bath, and the oxydizing operation repeated with the same proportion of nitric acid and chlorate of potash, until no farther change is observed. This is usually after the fourth time of oxydation. The substance is then to be dried, first in vacuo, and then at 100°. By placing the mixture in a flask exposed to sunlight, the change takes place more rapidly and without the application of heat. The formula of the body thus obtained is C22H4O10, or, as the author writes it, CH4O5. Its crystals belong either to the right or oblique prismatic system. It is insoluble in water, containing acids or salts, and very slightly soluble in pure water. It unites with alkalies, and the crystals have an acid reaction ammonia converts it into a transparent jelly, but the substance is not dissolved. Acids separate it from this combination, as a gelatinous mass resembling silica. Treated with deoxydizing agents, it is readily decomposed. When a solution of sulphate of ammonium or of potassium is poured upon the dry substance, a crackling sound is heard, and a body is formed resembling graphite. The crystals are decomposed with ignition on the application of heat, gases being evolved, and a black residue left, which resembles finely divided carbon. This substance the author proposes to term graphic acid. When graphic acid is heated in naphtha to about 270°, water and carbonic acid are given off, while the naphtha takes a deep red color. The residual substance resembles graphite and has the formula C44H2O8, or with the author's equivalents, C22H2O4. When this substance is heated in a current of nitrogen to a temperature of 250°, water is given off with a little carbonic acid; the substance remaining is found to have the formula C132H4O22 or C66H4011. This body may be exposed for several hours to a red heat in a current of nitrogen without losing all its oxygen and hydrogen. The author compares graphic acid with a remarkable compound of silicon discovered by Buff and Wöhler, which has the formula Si4H4O5, and which was obtained from the graphitoid form of that element. The properties of the two substances agree very closely, whence it may be inferred that the graphite compound is the same term in the system of carbon as the silicon compound in the system of silicon. The total weight of graphite which in the compound is combined with atoms of hydrogen and of oxygen is 132. If we assume that this weight is like the corresponding weight, 84 of silicon, to be divided into four parts, we arrive at the number 33 as the atomic weight of graphite. Representing this weight by the letters Gr, the formulas of the substances C11H4O5, C22H2O4, and C66H4011 become Gr4H4O5, Grs H2O4 and Gr24H4011, where 0=16. According to the law of Dulong and Petit, the specific heats of the elements are inversely as their equivalents. The elements are divided into two classes, one in which the product of the specific heat into the equivalent is about 3.3-the other in which this product is 66. The specific heat of carbon in the form of graphite-0·20187-presents a remarkable exception to the law, if we take its equivalent as 6 or 12, but if we assume the atomic weight of graphite as 33, we have for the product of the specific heat into the atomic weight, the number 6-6 which is according to the law of Dulong and Petit. The relation which exists between the atomic weights of boron, silicon and zircon, and that form of carbon for which a place may be claimed as a distinct element, graphon, is precisely the kind of numerical relation. which is found to exist between the weights of analogous elements. We have These considerations lead to the inference that graphite functions as a distinct element, forming distinct combinations with a distinct equivalent, viz: 33. How far this inference may be extended to the allotropic forms of other elements, experiment alone can decide.-Quart. Journal of Chem. Soc., vol. xii, p. 261. [Note. With respect to the numerical relations between the eqs. of boron, silicon, graphon and zirconium which Brodie points out, it may be remarked that boron--at least with the equivalent 11-is triatomic, as shown by the density of the vapor of BCl3 and other considerations. It cannot, therefore, with this equivalent, belong to the same natural group with silicon and zircon, which are diatomic, as shown by recent investigations. Marignac has established the isomorphism of SnF2+KF with SiF2+RF, while Troost and Deville have shown from the vapor-density of chlorid of zirconium that its true formula is ZCl2-2 vols. or Z2C14 if we assume that all compounds correspond to 4 vols. in a gaseous state. The vapor density of SiCl2 also agrees with the supposition that silicon is diatomic, supposing it to represent 2 vols. The true equivalents of silicon and zirconium become therefore respectively 14 and 44 or 28 and 88, if we admit the 4-volume theory. The equivalents of carbon, silicon and zirconium are then to each other as 6, 14 and 44, or as 12, 28 and 88, the common difference being 8 or 16 nearly. The formula Si4H4010 was deduced by Buff and Wöhler upon the supposition that the equivalent of silicon is 21, the element being triatomic as assumed by Berzelius. But if we take 14 as the true equivalent, the formula for the same compound becomes Si6H4010, and comparing with this the formula C22H4010 we have 132 parts by weight of carbon, representing 6 eqs. of graphon instead of 4, as assumed by Brodie. This gives 22 as the equivalent of graphon, instead of 33. If now we multiply the spec. heat of graphite as found by Regnault, namely 0-201, by 22 we have 4.4 so that the spec. heat of an atom of graphon does not obey the laws of Dulong and Petit, as the product should be either 33 or 66. It may, however, be remarked that the spec. heat of graphitoid silicon has not yet been determined, and that there may be other classes of elements whose atoms have the intermediate spec. heats 44 and 55. The formulas of Brodie's compounds become, if we take the equivalent of graphon as 22Gr6H4O10, Gr12H2O8, Gr18H4O22, (taking 0-8 and not with Brodie as 16). No probable relation can be pointed out between the numerical values of the equivalents of graphon and of other elements, until we know to what natural group graphon belongs, since it is not certain or even very probable that the allotropic modifications of the same element belong to the same group.-w. G.] W. G. 4. On the Cause of Color and the Theory of Light; by Mr. JOHN SMITH, M.A. (Read by his brother, Dr. R. A. Smith).—The author, in attempting to explain certain natural phenomena, could not satisfy himself by applying the principles of either theory of light, and said that many natural phenomena indicated beats or vibrations in the luminous ether very |