contained ethyl benzoate, on being treated with potassium hydrate, evaporating to dryness to remove the alcohol, re-solution in water, and precipitation with hydrochloric acid, afforded benzoic acid abundantly. The reaction, therefore, is as follows: 3 6 5 By using mono-bromo-toluol (¤ ̧H. {CH3), toluic acid CH3 Br (¤.H. {€€,H,) with a trace of another acid perhaps iso 4 2 meric with it, was obtained. With the isomeric benzyl bromid (CH,(CH2Br)) the reaction yields a more complicated product. In a more recent paper, Wurtz shows that the acid mentioned above as obtained simultaneously with the toluic, is iso-toluic acid; and that its presence is due to the fact that the bromo-toluol used, contained an isomeric body. The substance obtained by acting upon benzyl bromid or chlorid, he finds to have the composition € 15H1402, and he gives it the name di-benzyl-carboxylic acid. In a second operation, 252 grams benzyl chlorid, 108 grams ethyl chlorocarbonate and 8,000 grams one per cent sodium-amalgam, were heated on a saline bath, with an upward condenser, till the whole mass was solid. This residue was extracted with ether, the ether distilled off till the temperature rose to 180°, the fluid remaining in the retort decomposed with alcoholic potash, the the alcohol evaporated, the residue dissolved in water, precipitated by hydrochloric acid and recrystallized from water. It separated in drops which solidified to a mass of fine needles. It is almost insoluble in cold water, and but little soluble in hot; alcohol and ether dissolve it readily. At 84° it melts and at a higher temperature distils. Its vapors are aromatic and irritating. To produce it, Wurtz assumes that under the influence of the sodium, the chlorid, by the loss of hydrochloric acid, becomes chloro-di-benzyl €1H,CH2 €.H, CHCI and that this by the simultaneous action of the so 6 dium and the ethyl chlorocarbonate becomes ethyl di-benzyl-carb-Comptes Rendus, lxviii, 1298; oxylate lxx, 350. 6 5 4 G. F. B. 16. On the volatile acids of Croton oil.-Froelich having observed in the Jena laboratory, that by the action of phosphorus pentachlorid upon ethyl-diacetic acid, two metameric chlor-acids were obtained, yielding when treated with sodium-amalgam, two metameric acids of the composition H2, of which one was solid and identical with that prepared from allyl cyanid, the other was fluid, and supposed to be the same as that described by Schlippe as occurring in Croton oil, and called Crotonic acid, GEUTHER undertook a confirmation of this supposition. Having prepared the volatile acids from four pounds of Croton oil, he finds that no volatile acid of the composition CH.2 exists in this oil, and that the solid acid contained in it is not angelic acid; and there 6 fore, that Schlippe's statements are entirely erroneous. The volatile fluid acids are essentially acetic, butyric and valeric, mixed perhaps with traces of oenanthic acid and higher members of the oleic series. The solid acid supposed by Schlippe to be angelic acid, is a metamer of it, to which Genther gives the name Tiglic acid. It constitutes more than a third of the volatile acids of Croton oil, and forms a barium salt readily soluble in water, crystallizing in pearly plates, and having the composition €1,Ba'2+5H2O. It has a remarkably close correspondence in properties with the methyl-crotonic acid of Frankland and Duppa. It is therefore obvious that the name "crotonic" given to the acid CH.2, is a misnomer, since croton oil contains no acid of this composition. Geuther therefore proposes to call the chlor-acid of Froelich, mentioned above, which fuses at 59.5° and boils at 194-8°, monochlor-quartenic acid, and the acid derived from it by the action of sodium-amalgam, which is fluid at 15° and boils at 171.9°, quartenic acid. For the metamer of the chloracid, melting at 94° and boiling between 206°-211° with partial decomposition, he proposes the name mono-chlor-tetracrylic acid; and for its derivative H2, first prepared from allyl cyanid and till now called crotonic acid, the name tetracrylic acid. Its aldehyd called croton-aldehyd by Kekulé, would therefore be tetracryl-aldehyd.-Zeitschr. Chem., II, vi, 26, Dec. 1869. 4 6 G. F. B. 17. On the Rhenish creosote from beech-wood tar.--Under the direction of Baeyer and Graebe in Berlin, MARASSE has made an investigation of beech-wood creosote, with results far more satisfactory and conclusive than had been previously obtained. The material on which he worked came from the manufactory of Dietze & Company in Mayence; it was colorless, a little thick, heavier than water, in which it was scarcely soluble, and dissolved completely in potassium hydrate solution. On subjecting it to fractional distillation, three separate products were obtained: one boiling below 199°, one between 2000 and 203° (by far the larger portion) and one between 216° and 220°. After drying the lightest product, and subjecting it to sixteen fractional distillations, a body was obtained, which boiled between 183° and 184°, solidified on cooling, and had the properties of phenol, which an analysis proved it to be. On distilling the second and largest fraction with zinc-dust and purifying and fractioning the distillate, two products were obtained; the one, boiling between 110° and 112°, proved on analSince the zinc-dust acts ysis to be toluol‚¤‚H ̧, or € ̧н ̧ { CH ̧ ̧ 7 6 4 H by reducing hydroxyl to hydrogen, the body yielding this toluol must have been €,H,CH 3 or cresol. The other portion boiling 6 4 at 150° to 155° afforded the properties and composition of anisol. As this anisol €€н, SH does not exist in the creosote as such, 6 4 it must have been produced by a similar action of the zinc-dust, ( ᎾᎻ from the body €.H.OCH, 4 which is guaiacol, the acid methyl 6 That the fraction boiling be ( ᎾᎻ tween 200° and 203° was thus composed, Marasse further proved by fusing it with potassium hydrate. Two liquids were thus obtained which on examination proved to be cresol itself (CH3, and pyro-catechin HOH ¤ ̧H1 { the latter produced ᎾᎻ by the saponification of its ether, guaiacol, in the experiment. The same result was reached by acting upon this fraction with hydriodic acid; cresol and pyro-catechin being produced as before. And finally, by acting upon this fraction with methyl iodid and potassium hydrate in sealed tubes, the methyl ethers of both cresol JOCH, 3 (cresyl-anisol €,H,{C) and guaiacol (CH. {CH;) were 4 3 obtained. The last fraction, boiling between 217° and 220°, afforded, after reduction with hydriodic acid and fractioning, phlorol, CH3 CH3 €,H,, or CH, CH, and homo-pyro-catechin €,H2 →н, 8 10 ᎾᎻ 3 3 ᎾᎻ which last substance was derived from creosol, its acid methyl CH. 3 ether CH, 6 CII, precisely as pyro-catechin was in the previous ᎾᎻ fraction, from guaiacol. Marasse hence concludes that Rhenish beech-wood creosote is a mixture of compounds belonging to two parallel series, the phenols and the acid methyl ethers of pyro-catechin and its homologues. And since the first members of the series do not coincide in boiling point, the first member of the guaiacol series agreeing with the second member of the phenol series, it is obvious that that portion of creosote which boils at the lowest temperature will consist of the first member of the phenol series, i. e., phenol itself. ᎾᎻ €H, 3 Boiling point. 200° C. Phlorol, CH CH2 220° Creosol, CH, CH, 219° 3 All the different kinds of beech-wood creosote appear to be identical in composition; those specimens having the highest boiling point, which contain the higher members of these parallel series.— Ann. Ch. Pharm., clii, 59, Oct., 1869. G. F. B. 16. On Ocean Currents, in relation to the Distribution of Heat over the Globe, by JAMES CROLL of the Geological Survey of Scotland. (Phil. Mag., Feb. 1870.)-I. The absolute Heating-power of Ocean-currents. ***From an examination of the published sections [of the Gulf Stream] some years ago,* I came to the conclu* Philosophical Magazine for February, 1867, p. 127. sion that the total quantity of water conveyed by the stream is probably equal to that of a stream 50 miles broad and 1000 feet deep,* flowing at the rate of four miles an hour, and that the mean temperature of the entire mass of moving water is not under 65° at the moment of leaving the Gulf. I think we are warranted to conclude that the stream, before it returns from its northern journey, is on an average cooled down to at least 40°; consequently it loses 25° of heat. Each cubic foot of water, therefore, in this case carries from the tropics for distribution upwards of 1500 units of heat, or 1,158,000 foot-pounds. According to the above estimate of the size and velocity of the stream, 5,575,680,000,000 cubic feet of water are conveyed from the Gulf per hour, or 133,816,320,000,000 cubic feet daily. Consequently the total quantity of heat transferred from the equatorial regions per day by the stream amounts to 154,959,300,000,000,000,000 foot-pounds. From observations made by Sir John Herschel and by M. Pouillet on the direct heat of the sun, it is found that, were no heat absorbed by the atmosphere, about 83 foot-pounds per second would fall upon a square foot of surface placed at right angles to the sun's rays. Mr. Meech estimates that the quantity of heat cut off by the atmosphere is equal to about 22 per cent of the total amount received from the sun. M. Pouillet estimates the loss at 24 per cent. Taking the former estimate, 64-74 foot-pounds per second will therefore be the quantity of heat falling on a square foot of the earth's surface when the sun is in the zenith. And were the sun to remain stationary in the zenith for twelve hours, 2,796,768 foot-pounds would fall upon the surface. It can be shown that the total amount of heat received upon a unit surface on the equator during the twelve hours from sunrise till sunset at the time of the equinoxes is to the total amount which would be received upon that surface, were the sun to remain in the zenith during those twelve hours, as the diameter of a circle to half its circumference, or as 1 to 1.5708. It follows, therefore, that a square foot of surface on the equator receives from the sun at the time of the equinoxes 1,780,474 foot-pounds daily, and a square mile 49,636,750,000,000, foot-pounds daily. But this amounts to only 12t75 part of the quantity of heat daily conveyed from the tropics by the Gulf-stream. In other words, the Gulf-stream conveys as much heat as is received from the sun by 3,121,870 square miles at the equator. The amount thus conveyed is equal to all the heat which falls upon the globe within 63 miles on each side of the equator. According to calculations made by Mr. Meech, the annual quantity of heat received by a unit surface on the frigid zone, taking the mean of the whole zone, is 5 of 12 *The Gulf-stream at the narrowest place examined by the Coast Survey, and the place where its velocity was greatest, was found to be over 30 statute miles broad and 1950 feet deep. But we must not suppose this represents all the warm water which is received by the Atlantic from the equator; a great mass of water flows into the Atlantic without passing through the Straits of Florida. + Trans. of Roy. Soc. of Edinb., vol. xxi, p. 57. Phil. Mag., S. 4, vol. ix, p. 36. Smithsonian Contributions to Knowledge, vol. ix. that received at the equator; consequently the quantity of heat conveyed by the Gulf-stream in one year is equal to the heat which falls on an average on 6,873,800 square miles of the arctic regions. The frigid zone or arctic regions contain 8,130,000 square miles. There is actually, therefore, nearly as much heat transferred from tropical regions by the Gulf-stream as is received from the sun by the entire arctic regions, the quantity conveyed by the stream to that received from the sun by those regions being as 15 to 18. But we have been assuming in our calculations that the percentage of heat absorbed by the atmosphere is no greater in polar regions than it is at the equator, which is not the case. It we make due allowance for the extra amount absorbed in polar regions in consequence of the obliqueness of the sun's rays, the total quantity of heat conveyed by the Gulf-stream will probably nearly equal the amount received from the sun by the entire arctic regions. If we compare the quantity of heat conveyed by the Gulf-stream with that conveyed by means of aërial currents, the result is equally startling. The density of air to that of water is as 1 to 770, and its specific heat to that of water is as 1 to 4.2; consequently the same amount of heat that would raise 1 cubic foot of water 1° would raise 770 cubic feet of air 4°.2, or 3234 cubic feet 1°. The quantity of heat conveyed by the Gulf-stream is therefore equal to that which would be conveyed by a current of air 3234 times the volume of the Gulf-stream, at the same temperature and moving with the same velocity. Taking, as before, the width of the stream at 50 miles, and its depth at 1000 feet, and its velocity at 4 miles an hour, it follows that, in order to convey an equal amount of heat from the tropics by means of an aërial current, it would be necessary to have a current about 14 mile deep, and at the temperature of 65°, blowing at the rate of four miles an hour from every part of the equator over the northern hemisphere towards the pole. If its velocity were equal to that of a good sailingbreeze, which Sir John Herschel states to be about twenty-one miles an hour, the current would require to be above 1200 feet deep. A greater quantity of heat is probably conveyed by the Gulf-stream alone from the tropical to the temperate and arctic regions than by all the aërial currents which flow from the equator. The anti-trades or upper return-currents, as we have seen, bring no heat from the tropical regions. After traversing some 2000 miles in a region of extreme cold they descend on the Atlantic as a cold current, and there absorb the heat and moisture which they carry to northeastern Europe. Those aërial currents derive their heat from the Gulf-stream, or if it is preferred, from the warm water poured into the Atlantic by the Gulf-stream. How, then, are these winds heated by the warm water? The air is heated in two ways, viz: by direct radiation from the water, and by contact with the water. Now, if the Gulf-stream continued a narrow and deep current during its entire course similar to what it is at the Straits of Florida, it could have little or no opportunity of com |