boniferous period. Again it sank, carrying with it its store of decayed and decaying vegetation, and another flood of pebbles rolled over it.

How many ages were consumed in the process so briefly described, who can tell? Nature's operations are on too vast a scale, and her working time too long to admit of hasty activity in the production of results. It may well be said that all the years since the creation of man would be too short a time to produce a bed of coal.

However long the process just described, it was of frequent repetition during the coal period; and thus we find pebble-beds, slate and coal in often recurring series, as in the following cross-section made at Trevorton, the western terminus of the middle Anthracite coal basin.

But through all the changes of time and scene, the upheavals and depressions, the submergence and emergence of the land, we find a remarkable uniforformity in the growth of plants, continuing almost without change throughout; sigillaria, lepidodendra, ferns, etc., following their kind, unvaried through successive series of strata, in each leaving their character istic impress of stems and foliage on the enduring tables of the rocks. The coal flora is rich in variety and of great beauty, as Professor Lesquereaux's careful research abundantly testifies. Their exact forms show a quiet condition of the waters, at least during the deposit of the slate covering of the coal beds; and the intervening rocks show the same facts. When impressions of the flora are found in the solid coal itself, we have the same evidence; but this is of rare Occurrence. The best impressions usually occur in the smooth top slate covering the coal beds.

When we examine the arrangement of the Pennsylvania Anthracite beds we wonder at their complexity. Without evidence of volcanic disruption, not even a protruded trap-dyke, or extensive up or down throw, we often find contortions and disturbances of the strata. The beds are rarely horizontal, but lie at every angle, and sometimes even pass the perpendicular and fold back upon themselves. In places they occupy our mountain summits, nearly 2,000 feet above the level of the sea, and again depressed more than 3,000 feet below it, making a variation of a mile in altitude. Yet the coal, which is the frailest material in all this rocky mass, is not destroyed, but generally in good workable condition-solid, almost crystalized, almost pure carbon, and frequently in beds too thick for economical working.

Faults in the Anthracite beds usually have a northwest and southeast direction, and show the beds compressed, and again correspondingly enlarged, but no sudden dislocations or breaking off of the strata. Soft coal, or dirt faults, are of common occurrence in the red ash or softer coals in the western end of the Anthracite fields.

The colored ash of burned coal is due, doubtless, to the presence of iron; but why this coloring matter is confined to the upper series of coals in the eastern portion of the range, and to the lower beds in the western district; and why there is a gradation in the middle district, from white ash in the lower to grey in the middle and red in the upper beds, are problems yet to be solved.

How shall we account for the great disturbance of the strata from their original horizontal position? Was it caused by volcanic force-of which there are no indications-or by contraction of the earth's crust? And if the latter, why is it confined to the Anthracite region, and not extended to the Bituminous also? And how shall we explain the isolation of the smaller coal fields, like those of Rhode Island, Richmond, Va., or Deep River, in North Carolina; or the disproportion in quantity between the limited area of Anthracite and the widespread fields of Bituminous ? Why do we find an abundance of shells and remains of animal life in the latter, and rarely any in the former? A few saurian footprints recently found at the Ellangowan Colliery, in Schuylkill County, and a few shells found in the Glendower Pit, in the Wyoming Valley, are signal exceptions to an almost universal rule. After an exploration, covering the period from 1835 to 1850, Prof. H. D. Rogers and his corps of assistants failed to find any other specimens. Neither has Prof. Lesley in his new Geological Survey of Pennsylvania, or the writer in an experience of thirty years' residence and active service, underground and in surface explorations, been any more fortunate. bed of iron or limestone, and scarcely a covering of Nor in all this area do we find a single workable fertile soil. The coal once exhausted, nothing is left but the worthless shell, desolate and deserted.

The Anthracite region, mainly confined to one-sixth the area of the four mountainous counties of Luzerne, Schuylkill, Carbon and Northumberland, in Pennsyl vania, is crowded with an industrious population which increased fifty-one per cent in ten years; that is, from 229,700 in 1860 to 344,771 in 1870; whilst the four adjacent agricultural counties of similar area increased in the same time from 319,542 to 339,942, only six per cent. It is located on the parallel of 40° 30', one hundred miles from any seashore, no part of it less than 500 feet above tide-near the headwaters of the large rivers that drain it-the Susquehanna, Schuylkill, Lehigh and Delaware. The noisy trains crossing the valleys and climbing the mountains all verge, day and night, to these hives of industry, where multitudinous steam engines are hoisting and pumping, and breakers crushing. Thousands of miles of railroad thread the surface and dive into the interior, to roll out the black diamond flood in millions of tons of fuel to warm and employ the nation.

In a second paper, I propose to offer some important statistics and information regarding the harvesting of coal.

As a supplement to articles in the last November and January numbers of the American Journal of Science, John M. Stockwell details his investigations into the general theory of the moon's motion as affected by the sun's attraction. While taking a rather despondent view of our present knowledge of the factors in lunar calculation, he admits that the general methods of computation are undoubtedly correct.

J. M. STILLMAN, in August Journal of Science, describes the appearance of a new resinous substance in a rocky matrix, from San Barnadino, Cal. It is found in detached masses, in vein form, over a distance of three miles. He seeks to explain its existence by ascribing it to exudations from existing conifers, but does not account for its paragenesis.

SCIENCE:

A WEEKLY RECORD OF SCIENTIFIC PROGRESS.

JOHN MICHELS, Editor.

PUBLISHED AT

229 BROADWAY, NEW YORK.

P. O. Box 8838.

SATURDAY, AUGUST 21, 1880.

To Correspondents.

much really good scientific work can be done with limited means when directed by intelligence well applied.

The State of New York can boast of twelve obser

vatories, Michigan four, Pennsylvania three, Massachusetts, Connecticut, Ohio, Missouri, Iowa, each two, and Tennessee, California, Mississippi, Minnesota, Indiana, Kansas, Illinois, Maryland have each one observatory. It will thus be seen what an immense territory is covered by American astronomers, ranging from the shores of the Atlantic to the Pacific coast, and from the tropical regions of the Gulf of Mexico to Lake Superior on the North. Many of these observatories are supplied with requisite appliances of the most perfect description, while all, with one exception, have at least a good achromatic astronomical telescope.

For the benefit of those who desire to promote astronomical research, we may state that the single ex

O., New York-with name and address of writer, not necessarily for publication without consent.

Scientific papers and correspondence intended for publication, should be written legibly on one side only of the paper. Articles thus received will be returned when found unsuitable for the Journal.

Those engaged in Scientific Research are invited to make this Journal the medium of recording their work, and facilities will be extended to those desirous of publishing original communications possessing merit. Proceedings of Scientific Societies will be recorded, but the abstracts furnished must be signed by the Secretaries.

Both questions and answers in "Notes and Queries" should be made as brief as possible; an answer appearing to demand an elaborate reply, may be written in the form of an article.

AMERICAN ASTRONOMICAL WORK.

The progress of science in the United States cannot be better illustrated than by a brief review of the astronomical work now in progress, and the instruments at the command of those making observations in this country.

Taking as our authority the "Report on Observatories," published by the Smithsonian Institution, and the "Annual Record" prepared by Professor Edward S. Holden, of the U. S. Naval Observatory, Washington, we find that in seventeen States Astronomical Observatories are located, varying in degree of importance from the National Observatory at Washington, to the possessor of a two-inch achromatic telescope of its owner's own make. The work done with the latter instrument being most instructive as showing how

scope, is that of the Ohio State Observatory, the director of which is Professor R. W. McFarland, who states that he "was trying to get the authorities to do something," apparently with poor results.

Among the largest equatorials directed nightly to survey the heavenly bodies may be mentioned the great 26-inch instrument, by Messrs. Alvan Clark & Sons, at the Naval Observatory at Washington, under the charge of Professor Asaph Hall (who has already made such important discoveries with it), assisted by Professor Edward S. Holden; the Dearborn Observatory at Chicago possesses an 18-inch equatorial (Alvan Clark); Harvard University employs a 15-inch equatorial by Mertz; the Allegheny Observatory, Pennsylvania, has a 13-inch instrument (Alvan Clark); the Morrison Observatory, Glasgow, Missouri, uses a 12-inch instrument (Alvan Clark); Professor Lewis Swift at Rochester, New York, has charge of a 16inch equatorial (Alvan Clark); the lady Professor of Vassar College, Poughkeepsie, has an excellent equatorial of 123-inch (Alvan Clark), while lastly, Dr. Henry Draper at Hastings, N. Y., owns a 12-inch instrument, also by Alvan Clark.

This powerful battery of astronomical telescopes of the highest excellence might seem to be sufficient for one nation, but the national spirit of American enterprise appears to be strongly infused into this great branch of scientific research, for new astronomical telescopes of mammoth proportion and exquisite perfection are now in course of construction for United States observatories, which, in the hands of the able astronomers ready to receive them, will doubtless add to their already well-earned fame and the prestige of science in this country.

With these facts before us, we read without surprise the note by Professor O. Stone in our last issue, in which he says of a recently published "Record of the Progress of Astronomy during the year 1879," by Mr. Deyer, of Dublin, one-third of the memoir is devoted to the result of astronomical work done in the United States.

An article on this subject would be incomplete without a reference to the very perfect work of Messrs. Alvan Clark & Son, of Cambridge, Mass., who appear to have distanced both the English and the Continental opticians in the excellence of their objectives,

and who have secured to the United States the honor of supplying the objective for the great equitorial about to be manufactured for the Russian Government, to be used in the Pulkowa Observatory by the distinguished astronomer, Otto Von Streuve. We also notice that of the forty observatories recognized by the Smithsonian Institute, seventeen have telescopes made by this firm. In regard to the work now in progress at the Messrs. Clark's establishment, it may be stated without exaggeration that the world awaits with eager expectancy the result of their labors.

We record with pleasure the very perfect harmony with which American astronomers co-operate and work, which has doubtless been a leading point in gaining the successes that have been attained. This is in strong contrast with the constant bickering among members of the Royal Astronomical Society and many English astronomers, some of whom have not thought it humiliating to charge the Astronomer Royal with ignorance, and a stubborn adhesion to error, and to allege that members of the council of the Royal Astronomical Society suppress the papers of their fellow members from personal and unworthy motives.

Of American astronomers, it might seem invidious to make a personal reference to particular men, but the names of Newcomb, Hall, Eastman, Holden, Stone, Burnham, Draper, Swift and Rutherford are familiar in all civilized countries, and respected wherever the science of astronomy is appreciated.

A NEW ELECTRIC PILE DEVISED BY M. REYNIER.

Translated for "SCIENCE."

M. Emile Reynier, the electrician, and inventor of an electric lamp, which we have more than once had occasion to present to our readers, and which its author has never ceased to improve and perfect, with the view of making its use more satisfactory, more convenient, and more economical, has now arranged a pile, which is at the same time powerful and economical. This apparatus is composed of a glass vessel in the form of an oblong square, in which is immersed a sheet of copper bent upon itself, as shown in Fig. 1. Upon the bottom of this copper hook rests a cup of parchment, into which the zinc plate is placed, as shown in Fig. 2.

FIG. 1.-THE COPPER PLATE OF THE PILE OF REYNIER. FIG. 2.-THE ZINC PLATE OF THE PILE OF REYNIER. This vessel or porous diaphragm has this peculiarity, that it is made up of a conical sheet of parchment, and that corresponding with the rectangular or octagonal form, just as may be chosen, it is folded upon itself (Figs. 3 and 4) as indicated by the tracings of the diagrams (Figs. 5 and 6). The strongly marked lines in the figures represent the folds of the angles, the figures indicating the faces, whilst the lighter lines represent the intermediate folds which insure the stability of the system.

M. MASCART has been making some observations at the College of France, on atmospheric electricity, with a Thomson quadrant electrometer, the deflections of the needle being transmitted to a pencil. The two pairs of quadrants are kept at equal potentials of contrary sign by two poles of a battery which communicate with the ground; the needle is connected with a vessel letting flow a continuous stream of water into the outer air. Generally the potential of the air, always positive, is found much higher, and more uniform by night than by day. From 9 P. M. to 3 A. M,, it varies little, falls at daybreak, reaches a minimum about 3 P. M., and rises rapidly to a maximum about 9 P. M. It is commonly thought that there are two maxima, viz. morning and evening, and two minima, one in the day. time, the other at night. M. Mascart believes that insulation has been too much neglected.

hydro-electric, is superior, as a working electro-motor, to the Daniell pile, of sulphate of copper and sulphate of zinc; of equal size, and is about twice as powerful as the ordinary Bunsen pile of the laboratories, and is only surpassed by the special form of the Bunsen pile, devised by Ruhmkorff.

"The zinc is not amalgamated," says M. Reynier in his note to the Academy of Sciences, "nevertheless, it is not attacked when the circuit is open by the alkaline solution which bathes it; consequently, the quantity of zinc consumed must give precisely the measure of the amount of elec

tricity disengaged. The new pile" he adds, "does not send off volatile products; hence the materials employed are not subject to waste. It is therefore possible to regulate the products of the chemical changes, and they may even be restored to their original state. It is necessary, to do this, to cause a quantity of electricity a little greater than that which has been disengaged by the pile, to traverse the exhausted liquids, dissolving the copper displaced, and removing the zinc dissolved. This renewal of the materials of the pile restores its electro-motor qualities. When elec

FIG. 7.

FIG. 7.-REYNIER'S PILE COMPLETE.

M. Reynier's pile has been submitted to repeated trials, notably by the Société Française de Physique, with fifty couples or elements; the inventor operated successively a voltameter, the electric motors of Gramme and of Deprez, a large Ruhmkorff coil, and an electric lamp with Serrin's regulator. A platinum wire 65 centimetres in length and half a millimetre in diameter, was maintained at a white heat for more than an hour, while the galvanometer failed to show the slightest decrease of power in the pile.-La Science pour Tous.

M. POINCARE presented to the Academy of Sciences, Paris, the results of an investigation of butcher's meat, in which he found cylindrical pointed elements with cuticles crossed by lines which seem outlines of cells, and which appear granulated. He thinks they may be phases or metamorphoses of tænioides, causing tænia in some eaters of

raw meat.

DR. J. LAWRENCE SMITH has determined and named the new mineral Peckhamite found on the outer surfaces of the remarkable meteorite whose fragments were sown across the borders of Dickenson and Emmet Counties in northwestern Iowa. By an average of two of Dr. Smith's analyses it contains 49.55 per cent. silica, 16.44 per cent. ferrous oxide and 32.76 per cent. magnesia. By calculation of the oxygen ratio the formula SiO2RO+ (SiO,R,O) would represent its composition, suggesting two atoms of Enstatite or Bronzite plus one atom of Olivine. This is one of the most interesting meteorites known. Over 5,000 fragments of it weighing about 30 kilograms, have been collected from over a distance of eight miles long by one-half mile wide. Although the lumps have been lying on the wet prairie for nearly a year, they are not in the least rusted, and bear a great resemblance to nuggets of platinum. Dr. Smith surmises the rapid passage of the meteorite through our atmosphere caused its disintegration, pulverizing the stony part completely and leaving the nodules of neckiliferous iron untouched. This hypothesis is novel and plausible.