omy. We only wish the publisher had done as well as the authors. The illustrations are numerous, and probably sufficient to fulfil the end of helping the student in his work; but, from an artistic point of view, they are, with rare exceptions, simply atrocious.

MINOR BOOK NOTICES.

Lon

Guesses at purpose in nature, with especial reference to plants. By W. POWELL JAMES, M. A. don, 1883. 192 p. 12°.

THIS is a little book of ten chapters, which has just reached us, and which we would notice with a word or two in addition to an announcement of its title. The author, we fancy, is a clergyman and merely an amateur naturalist. However that may be, his guesses are shrewd, and the way of putting them is taking. Considering the great number and variety of the facts he has collected, the greater part from books, he has fallen into few mistakes; so that the volume has more scientific value than is usual in such treatises.

An outline of qualitative analysis for beginners. By JOHN T. STODDARD, PH.D, professor of chemistry in Smith college. Northampton, Gazette printing company, 1883. 4+54 p. 16°. The general plan of this work will doubtless

be recognized as one which gives the best results in teaching qualitative analysis. To a certain extent it is faulty in detail, both as regards convenience of arrangement and the selection of methods. Although this criticism applies more especially to the course of basic analysis, if advantage were taken of differences in solubility of certain barium, calcium, and silver salts of the acids, it would save the student much time and labor in general analysis. An appended list of the names and symbols of the more common reagents will be found useful.

A short course on quantitative analysis. By JOHN HOWARD APPLETON, A.M., Brown university. Philadelphia, Cowperthwait & Co., 1881. 183 p., cuts. 12°.

The course of analysis presented in this work consists, with few exceptions, of a judicious selection of methods and determinations. The descriptions of processes and apparatus will undoubtedly be of much service in the laboratory, although considerable descriptive chemistry is introduced with which the student is supposed to be familiar before undertaking quantitative analysis. An exception will probably be taken to the completeness of the notes and explanations, which leave little opportunity for thought or study on the part of the student.

MATHEMATICS.

Alignment curves on the ellipsoid. Mr. C. H. Kummell describes several curves that represent the straight line, all of which, on the sphere, reduce to the great circle. The vertical section is traced by the surveyor at one end, who fixes points in range with the other end. The proörthode (ñрó, óрtós, óðós) results, if the alignment at each point is determined at a point previously fixed, the distance between the two being infinitesimal. It is followed in chaining, or more roughly by the pedestrian in moving toward an object. In these two curves no back-sight is taken: they are differently related to the two ends, and do not return upon themselves. The diorthode (dú) is the locus of all points at which the vertical plane through one terminal point also includes the other. It is used in laying out primary base-lines, the points of which are determined by making fore-sights and back-sights differ always by 180°. This curve has been confounded with the preceding by Dr. Bremiker (Studien über höhere geodäsie, 1869) and others; but the proörthode is everywhere tangent to the vertical plane passing through one terminal point, while the diorthode, except at the ends, is not. The curve of shortest distance between two points, often called the geodetic line,' would more properly be called the brachisthode (βράχιστος). These names were suggested by Mr. W. R. Galt of Norfolk, Va.

Mr. Kummell shows the diorthode to be the inter

section of the ellipsoid with a hyperboloid of one sheet. In the case of an ellipsoid of revolution, this is the parabolic hyperboloid. Taking the three principal axes, a, b, c, as axes of x, y, and z, he represents the points where the chord connecting the two termini of the proposed alignment pierces the planes xy, xz, yz, by (Xz, Yz, 0), (Xy, 0, zy), and (0, yx, Zx), respectively, and introduces quantities,

Testing insulation of electric-light wires. Mr. C. J. H. Woodbury described a compact piece of apparatus, consisting of a magneto-electric machine and a pair of electric bells. The machine will produce a current strong enough to ring the bells through a resistance of seven thousand ohms. By connecting one pole with the electric-light system, and the other with the ground, the insulation of the system may be shown to be more or less than about seven thousand ohms, according as the bells ring or not. The method has been found useful in the inspections now made in the interest of fire-insurance companies.. (Frankl. inst., meeting April 18.)

(812 Electrical transmission of power. - Dr. C. W. Siemens, in the course of an address at the Institution of civil engineers on March 15, after describing the well-known experimental electrical railways of the Berlin and Paris exhibitions, stated that an electrical railway six miles in length had just been completed in the north of Ireland. In this instance the two rails, three feet apart, were not insulated from the ground, but were joined electrically by means of copper staples, and formed the return circuit, the current being conveyed to the car through a T iron, placed upon short standards, and insulated by means of insulite caps. For the present the power was produced by a steam-engine at Portrush, giving motion to a shunt-wound dynamo of 15,000 Watts, or 20-horse power. The working-speed of this line was restricted by the board of trade to ten miles an hour, which was readily obtained, although the gradients of the line were decidedly unfavorable, including an incline of two miles in length at a gradient of 1 in 38. It was intended to extend the line six miles farther, in order to join another railway system. The electric system of propulsion was, in the lecturer's opinion, sufficiently advanced to assure practical success under suitable circumstances; such as for suburban tramways, elevated lines, and, above all, lines through tunnels. The lecturer, however, did not advocate its prospective application in competition with the locomotive engine for main lines of railway. - (Nature, March 29.) E. H. H. [813

ENGINEERING.

Stadia reductions. —Mr. Arthur Winslow presented, and described the derivation of, tables for stadia reductions, which furnish expressions for horizontal distances and differences of elevation, corresponding to 100-foot stadia readings for 2" up to 30°, on the supposition that the rod be held vertically, and the stadia wires be equidistant from the centre wire. They are not mere reductions of inclined distances to their horizontal and vertical components, but embody certain corrections necessary from the facts, 1°, that with horizontal sights the length cut off by the stadia wires on the rod is not directly proportional to its distance from the centre of the instrument, but from a point at a distance in front of the object-glass equal to its principal focal length; and, 20, that with inclined sights a correction has to be made for the oblique view of the rod. Both the distances and elevations in these tables are given in feet. They are adapted to use with a telescope whose object-glass has any focal length, and with a rod which is so graduated that the spaces cut off on it by the stadia wires are directly proportional to its distance from a point at a distance in front of

the object-glass equal to its principal focal length, differing in these respects from the tables issued by the engineer department, U.S.A.(Eng. club Philad.; meeting April 7.) [814

CHEMISTRY. (Organic.)

Constitution of atropine.-A. Ladenburg proved that tropine is a tertiary base, since it would not unite with more than one molecule of ethyl iodide, and it was not affected by nitrous acid. By the action of chlorhydropasic acid upon it, a tropasate of tropine was formed; and, when treated with dilute hydrochloric acid, the latter substance was converted into atropine, which separated in beautiful crystals on evaporating the solution.

This product proved to be identical, in its chemical as well as in its physiological characters, with natural atropine prepared from belladonna. A series of derivatives, called by the author tropeines, results from the action of various organic acids with hydrochloric acid upon tropine. To establish the constitution of tropasic acid, it was prepared by the action of potassic cyanide in alcoholic solution upon chloracetophenon, and treating the product with baric hydrate. The resulting atrolactinic (or tropasic) acid was also made from hydropasic, and it was converted into atropasic acid. Since, furthermore, atropasic was converted into tropasic acid, the formula of the latter must be CH,CHCH2OH. When distilled with soda-lime,

соон

tropine is decomposed, giving methylamine and tropilidine (C,H); and, when treated with fuming hydrochloric acid, a volatile base, tropidine (C,H13N), is formed. By the action of hydriodic acid and red phosphorus, hydrotropine iodide (C,H,,N I) results. Tropine is thus shown to contain an hydroxyl group; and the above-mentioned synthesis of atropine, and the formation of the tropeines, are explained: CH11NOH CHNO(CHO2) CHNO(CH2O2) Tropine. Atropine. Homatropine.

The tropeines are therefore ethers of tropine, which is a nitrogen-containing alcohol. When heated with bromine, tropidine is decomposed, with the formation of ethylen bromide and dibrompyridine (CH, Br2N). The author is at present engaged upon the synthesis of tropine from pyridine. (Ann. chem., ccxvii. 74.) (815

C. F. M.

Protocattannic acid and anhydrides of the aromatic oxy-acids. Hugo Schiff states, that, when protocatechuic acid in aqueous solution is boiled with arsenic acid, a substance is formed, with the formula of diprotocatechuic, or protocattannic acid (2 CH6O-H2O=C14H1007). The solution possesses the general reactions characteristic of tannin; and mineral acids reprecipitate protocatechuic acid. When protocatechuic acid in etherial solution is acted upon by phosphorous oxychloride, tetraprotocatechuic acid is formed (4 C,H60,- 3 H2O C2RH18013). The solution fluoresces, and its reactions in general are characteristic of tannin. If an intimate mixture of protocatechuic acid and dry arsenic acid is heated to 160°, a catelagic acid corresponding to elagic is produced (2 CHO1~(H2O+H2)=C14H1007).-(Gaz. chim. ital., 1883, 90; Berichte deutsch. chem. gesellsch., xv. 2588.) C. F. M.

(816

Action of cyanogen chloride on pyrrol-potassium. By the action of dry gaseous cyanogen chloride on pyrrol-potassium, Ciamician and Dennstedt find that the cyanogen molecule is introduced, forming cyanpyrrol or tetrolcyanamide. This substance polymerizes at the point of fusion, with the formation, probably, of tetrolcyanuramide or tetrolmelamine,

METALLURGY.

[817

Delta metal. - An alloy has been perfected by Mr. Alexander Dick of London, which is composed of copper, zinc, and iron. If ordinary wrought-iron is introduced into molten zinc, it will be taken up by the zinc to about five per cent of the quantity of zinc. This product is then added to copper, or to copper and zinc, in the desired proportions. The resulting alloy is said to be as much superior to brass as phosphor-bronze is to gun-metal. It has great strength and toughness. When cast in sand, its tensile strength is 21 to 22 tons per square inch. When drawn into wire of 22 W. G., its tensile strength is 62 tons to the square inch. (Iron, Feb. 23.) R. H. R. [818 Metallurgy of the Incas. At the meeting of the French academy on Feb. 6, M. Boussingault exhibited a bronze chisel harder than copper, but not so hard as iron, which was composed of 95 per cent copper, 4.5 per cent of tin, with traces of lead and silver. This tool is of a period previous to the conquest of the Incas by Spain. -(Iron, March 16.)

R. H. R.

[819

Soaking-pits. At the meeting of the Society of engineers, Feb. 5, Mr. Church, in his inaugural address, referred to the device of Mr. John Gjers, which consists in placing ingots of steel directly in so-called soaking-pits. The ingot being thus surrounded by hot walls, the surface-heat is increased, and it is rolled by its own initial heat. This not only saves fuel, but avoids all danger of burning in reheating.(Iron, Feb. 9.) R. H. R.

[820

Equalizers. The Pittsburg steel-casting company places the ingots in square-shaped pits of firebrick, six feet deep, three feet six inches square at the top, three feet at the bottom. On each side of the row of holes is a pair of Siemens regenerators for gas and air. The holes are heated to 2,000° F., and are filled with gas as a non-oxidizing atmosphere; and four ingots, weighing about a ton, are placed in each pit. The ingots being dark red or medium red outside and fluid inside, it is but a few minutes before they are equalized to a soft yellow, and are then in the best condition to roll to small billets, or to flanged rails. (Iron, March 2.) R. H. R. [821

AGRICULTURE.

-

Materials for manuring moors. A paper by Fleischer describes the utilization of the sewage and garbage of the cities of Groningen and part of Bremen, for the reclamation and manuring of the surrounding moors. The materials are made into a compost, said to be comparatively inoffensive, and shown by analysis to have considerable value as manure, and sold, to be transported by water to the place of use. The paper is specially interesting in its bearings on the question of the utilization of city sewage. - (Landw. jahrb., xii. 203.) H. P. A.

[822

Sewage irrigation. Gersen discusses at considerable length the various systems of sewage irrigation, and the reasons of their failures, and proposes a new method, in which the sewage is distributed

over the surface to be irrigated in underground iron pipes under pressure, from which it is distributed by means of portable pipes. The ground may be flowed, or the sewage may be sprinkled upon it in regulated quantities. No levelling, and but little preparation of the surface, is required, and all open ditches or settling-basins are avoided.—(Landw. jahrb., xii. 227.) H. P. Aș [823

Determination of available phosphoric acid. -Ollech and Tollens have continued the experiments by Grupe and Tollens on the use of citric acid as a reagent for the determination of available phosphoric acid. They recommend the use of a 14-per-cent solution of citric acid, 5 grams of phosphate, and 500 cc. water, and show that the phosphoric acid in the resulting solution can be precipitated directly with molybdic solution. - (Journ. landw., xxx. 519.) [824

H. P. A.

Cape Hatteras. Professor W. C. Kerr's studies in North Carolina have led to some interesting conclusions in regard to the geologic history of Cape Hatteras. The modern cape is a tract of low land which is, on one hand, losing altitude by subsidence, and, on the other, gaining it by accretion. The accretion is three-fold: first, sediment from local rivers; second, vegetable accumulation in a system of peat-forming swamps which occupy the divides between the streams; third, shore-drift, brought by the waves and currents of the Atlantic from the north and south. The shore-drift is derived from the sediment of the Susquehanna and other rivers, and is deposited in a continuous bank of sand, constituting the sea-front of the cape. The wind throws it up in dunes, which slowly travel landward, and eventually help to fill the lagoon, or sound, caused by the subsidence.

The history of the coast has not always been characterized by subsidence; for at various levels there are lines of shore-dunes and other coast features, which could have attained their present position only by an elevatory movement. One of the best preserved coast-lines has an altitude of less than 20 feet, and another, referred to the glacial epoch, lies at 500 feet.

When the ocean stood at the 20-foot level, the angle of the continental coast was at Cape Lookout, and before that it was at Cape Fear; but, though these great changes in the outline of the coast have occurred in very recent geologic times, the cape itself, considered as a salient of the continental margin, is not a modern phenomenon. It is at least as old the cretaceous; and since it is an accretionary grow dependent now on a certain combination of pre ing winds and currents, it affords presumptiv dence that a similar combination has charac this part of the Atlantic for several geologic -(Phil. soc. Wash., meeting April 7.)

pher. In the present paper he divides the schistose rocks into micaceous, hornblendic, and granulitic; and the microscopic characters of each group are given in detail. He endeavors to show the relation of the schistose rocks to the adjacent argillites, with which they have been supposed to be continuous. In the argillite he found a few fragments of the hornblendic rock, together with some felspathic fragments, which, he says, came from a metamorphic series. At another locality he found a fault (?) between the hornblendic rock and the argillite, at which the latter had been greatly broken. He states that the hornblendic rock here resembles a greenstone, but thinks he found in it signs of foliation and bedding. From this evidence he draws the conclusions that the argillites are younger than the metamorphic rocks by an enormous interval of time,' and that, while the former are devonian or older, the latter are azoic (archean). Without objecting at all to his conclusions, one may point out the requirements to prove them, which he has failed to give. He has not proved the schistose series to be sedimentary, but admits that part may be eruptive, and that some of the series, at least, may be formed from volcanic ash. Until the series is proved to be sedimentary, the finding of supposed fragments of it in the argillites is no proof of difference in age; for eruptive materials are always apt to be embedded in the rocks forming at the locality at the time of the eruption. Bonney has further taken foliation as bedding, with which it may or may not correspond, and assumes that a metamorphic is synonymous with a sedimentary rock, when in reality eruptive, especially basic, rocks are more easily metamorphosed than most sedimentary ones; and the former make a large part of the so-called 'metamorphic rocks' in many regions of crystalline schists. Until Bonney gives evidence to prove that his series is sedimentary, his conclusions cannot be regarded as established merely because he considers the rocks sedimentary.

The serpentine rocks of the Lizard district had been discussed in a previous paper, but additional material is given here. Bonney holds that the serpentine is formed from the alteration of an eruptive peridotite. That serpentine is formed by the direct conversion of olivine rocks has been conclusively shown by the work of numerous lithologists; and, in this particular case, Bonney's microscopic observations bear out the general conclusion. That the Lizard peridotite was eruptive was shown by its forming dikes in the adjacent rocks, by its distorting and displacing them, and by its enclosing fragments of them.-(Quart. journ. geol. soc., 1883, 1.) M. E. W.

METEOROLOGY.

[827

periments were made in a large open field at Strathfield Turgiss. Ten varieties of shelters were tried, eight of these being open, and two (Stevenson's and the Kew pattern) closed. It was found that all the open stands were subject to serious objections, as they gave varying results in different weathers. On the whole, the closed shelters were regarded as the better; and Stevenson's was preferred to the Kew, as the smaller and more easily handled. It is still thought, that, in dull weather, and for hygrometrical observations, this screen has not sufficient ventilation for the most accurate results. All the screens gave nearly uniform results for the mean tempera

ture. Experiments are now in progress for comparing wooden with Wild's metallic shelters. - (English quart. weath. rep., 1879.) H. A. H. [828

Terrestrial radiation. - Professor Tyndall placed a thermometer upon cotton-wool which lay on the ground, and suspended another four feet above it. On Nov. 11, 1882, at 6 P.M., the readings were: wool, 26° F.; air, 36°. There was nearly a dead calm, — sky clear, and stars shining. The observations were repeated on Dec. 10, when, at 8.20 A.M., wool read 120, and air 27°, with a clear sky, and very light wind. In both instances snow covered the ground. On many other days readings were made, and several of these with the sky perfectly clear, and with no visible impediment to terrestrial radiation; yet not onefourth of the difference was observed that occurred on Dec. 10. Prof. Tyndall seeks to explain these results by the hypothesis, long since advanced by him, that the invisible aqueous vapor of the atmosphere in the latter cases interposes an effectual barrier to radiation, and hence the difference. It would seem as though a few observations of the amount of vapor would have assisted in establishing or overthrowing this supposition.

In a later number Prof. Woeikof discusses these observations, and suggests that the snow had a marked effect in reducing the temperature of the air just above it. He thinks that aqueous vapor has only a slight effect in checking radiation; not, however, in its gaseous state, but when condensed in small ice-crystals or water-droplets, even if, which is sometimes the case, it is invisible to the eye. He also suggests, that, in order to determine the real effect of aqueous vapor in terrestrial radiation, observations should be conducted in a climate, where, with a relatively great tension of vapor, the relative humidity is so small that there is no dew on clear nights, or, at least, it appears very late. Three thermometers, on cottonwool, should be placed, one on the ground, and the others at heights from ten to a hundred feet above. If Prof. Tyndall's views be correct, the highest thermometer should show the lowest reading, as the aqueous vapor would impede radiation least from that one. He thinks there would be very little difference between the three thermometers. The matter is certainly worthy of careful experiment. (Nature, Feb. 15, March 15.) H. A. H. [829

PHYSICAL GEOGRAPHY.

Effects of deforesting in the Alps.-P. Demontzey describes, in a very well illustrated article, the injurious results following the cutting down of forests in the French Alps; these being chiefly the washing of great quantities of detritus down from the slopes, the rapid formation of gulleys and ravines, especially in the softer formations, and the inundation of good valley-land with sand and gravel. The extension of the torrential cone of the Rioubourdoux (Basses Alpes), where the mountain stream enters a broad valley, and several deep ravines, formed since 1830, on the branches of the Bourget, are excellently shown. The remedy adopted against further growth of the gulleys is to build numerous small dams across the side streams, and thus force the waters to drop their sediments, and build up their channels, instead of deepening them. Planting trees is to go on with this as fast as possible, to prevent the wearing of the bare hillsides. (La Nature, 1882, 151, 183, 215.) [830 Glacial erosion and lakes. Rev. A. Irving has recently read two papers before the London geological society, On the mechanics of glaciers, with special reference to their supposed power of excavation,

W. M. D.

and On the origin of valley lakes, with especial reference to the lakes of the northern Alps, coming to the conclusion that glaciers have not, and can not, cut out deep lake basins, although they may effect considerable general surface - erosion. Differential motions within the ice are regarded as consuming nearly all the gravitative and other force applied to the mass; so that an effective erosive motion of ice on bed-rock is small, and especially so in hollows where the motion is much retarded. The ice rather than the rock will yield when a stone is held between the two. Much rock-flour, washed away by the subglacial streams, may come from material carried down from surface-moraines. The author denies the force of Ramsay's argument that certain lakes cannot be explained save by ice-action, and thinks that certain possible causes were not sufficiently considered. Many alpine lakes are not at all where they should be, if formed by glaciers; and among the causes that may aid their formation are subsidence from underground solution, which recalls Playfair's old suggestion to account for Lake Geneva. This may be further aided by the simple weight of the ancient ice aiding to break down such undermined districts. Dislocations and folds, moraines, land-slides, and diluvial barriers, are also considered. Several special cases are referred to with some detail. (Quart. journ. geol. soc., 1883, 62, 73.) W. M. D. [831 Changes in the Mediterranean climate. - Dr. Th. Fischer, already known for his original studies in this direction, presents a brief statement of further work as supplementary to Tchihatcheff's entertaining lecture before the British association last August (v. Proc. roy, geogr. soc., 1882). His argument is based on the decline of population, shown by the numerous ruins in now desert regions of the northern Sahara, as well as in Asia Minor and farther east; on the barrenness of districts formerly cultivated, as is shown by the remains of irrigation-dams stretching across dry river-channels (wadis); on the occurrence in the Algerian desert of flint chippings covered by a thin gypsum layer, evidently the deposit of a spring, though the region is now wholly dry; and on the frequent occurrence of lightning-tubes in the dry sands, implying former frequent thunder-storms. In Algeria, the recorded annual rainfall from 1838 to 1849 averaged 800 mm.; from 1850 to 1862, 770 mm.; from 1863 to 1876, only 639 mm. The deforesting of the country is regarded as having aided this decrease. Furthermore, the absence of camels from old monuments in Egypt, the former occurrence of elephants in the northern Sahara, and use of horses and oxen in crossing the now desert region, all bear witness to the same general decrease of rainfall. (Peterm. mitth., 1883, 1.) W. M. D.

GEOGRAPHY.

(Arctic.)

[832

Aboriginal population of northern America. – A recently issued report on the Indians of the Dominion of Canada, together with the information collected by the tenth census of the United States relating to Alaska, affords the means of approximating to the aboriginal population of that part of North America, north of the boundary-line of the United States, as it existed in 1860. The Indian population of British Columbia, Manitoba (including the Northwest Territory), Athabaska, and Rupert's Land, being the regions where governmental supervision is nonexistent or comparatively recent, is put at 78,264. Athabaska and Rupert's Land contain about 6,000, the remainder being nearly equally divided between the other two districts. In the older provinces,

where the whites and aborigines have long been in contact, there are 32,241 Indians. Ontario has 17,126; Quebec, 11,089; Nova Scotia, New Brunswick, and Prince Edward's Island divide the remainder. There is an increase, in the total number, of 2,783 over that of last year. There are, of the total Indian population, 81,634 reported as living on reservations or under supervision.

In south-eastern Alaska, 6,725 Indians are reported; Cook's Inlet, Kadiak, and Prince William Sound are estimated to contain 1,028. The Kuskokwim valley is alloted 147; and the Yukon basin, 2,226. These latter figures are probably under-estimates; but the total arrived at is 10,126.

Of the Orarian or Eskimo population of the shores of arctic British America no enumeration is yet possible. From Labrador to the Mackenzie mouth, probably not less than 6,000 are scattered in various localities. In Alaska there are 2,214 Aleuts. Of Innuit, properly so-called, there are estimated to be 17,488, which is likely to prove excessive, and thus in the total to correct the supposed under-estimate of the Indian population. Of these, about 3,000 are assigned to the Arctic coast; about 2,000 to Cook's Inlet and Kadiak; 7,500 to Bristol Bay and the Kuskokwim delta; and 3,300 to the Yukon delta. Taken together, this would give 25,702 Orarians, and 120,631 Indians; or 146,333 aborigines for the whole area. As estimation enters into the figures in several places, it may be said in round numbers, that the region probably contains about 150,000 aboriginal inhabitants, or 1 to 65 kilometres.-W. H. D. 1833

Holdfasts in Podostemaceae. It is well known that the river-weeds possess organs by which they cling to loose stones much as Fuci do. Warming calls attention to the presence of root-hairs on these and many other kinds of holdfasts, and he proposes to bring the various sorts under a single designation, namely, Haptera. While the term may prove useful, it must be remembered that under it are comprised at least two unlike plant-members. As they fulfil the same office, namely, clinging, they are physiologically similar, although morphologically unlike. (Botan. zeit., March 22.) G. L. G.

(835