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try, and was for a time most actively pursued here, culminating in those beautiful photographs of the moon taken by Rutherfurd, as well as photographs of several double and multiple stars, and of the clusters Praesepe and the Pleiades. He told how Rutherfurd constructed a micrometer measuring engine, and obtained the first measures of the distances and position-angles of stars upon photographic plates, and how the work was received with considerable skepticism abroad. The speaker then described his own continuation of this same kind of work at Cordoba, and stated that he had brought home plates whose measurement would take a lifetime. Dr. Gould thought that he had the records of many 11th magnitude stars on his plates, the first photographs of such faint stars. Few of the plates were yet measured, and he was becoming solicitous about obtaining the necessary funds to proceed as rapidly as possible with this measurement, as he had detected a tendency, in some of the plates, of the collodion film to become detached from the plates.

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A paper by Mr. E. F. Sawyer, entitled Some account of a new catalogue of the magnitudes of southern stars,' was presented. Mr. Sawyer has been observing the relative magnitudes of all the stars between the equator and -30°, using an operaglass with the stars slightly out of focus, and employing Argelander's method. Dr. Gould paid a high compliment to Mr. Sawyer's work, as did also Mr. Chandler.

A paper by Dr. Elkin, of the Yale college observatory, upon A comparison of the places of the Pleiades as determined by the Konigsberg and Yale college heliometers,' was presented by Professor Newton. The results given were provisional; but they show unquestioned change of position with reference to ŋ Tauri since 1840. Most of the brighter stars of the group, as shown by Newcomb in his catalogue of standard stars' go with 7 Tauri, but among the smaller stars there are unquestioned departures from this community of proper motion.

In Monday's session a paper by Professor Abbe created some discussion. The point of the paper was, that, as the force of gravity varied from the equator to the poles, thirty inches of mercury in the barometer indicated a less gaseous pressure, and consequently less density of the atmosphere, at the equator than thirty inches at the poles, and hence a correction for latitude should be introduced in allowing for refraction. He showed that, for the difference of latitude of Pulkowa and Washington, it would make 0".1 difference in the refraction at 45° of zenith-distance, and might be sufficient partly to account for differences in systems of star declinations which depended upon observations at great zenith-distances.

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The most important paper in the section, and the one that attracted the most attention and discussion, was by Mr. Chandler, of Cambridge, upon 'A comparative estimate of methods and results in stellar photometry.' We have not space to do justice to this valuable and rather revolutionary paper, but we will try briefly to give its gist. Prefacing his remarks with the statement that it had long been known that small differences of stellar magnitude could be determined very accurately by Argelander's method of steps, by naked-eye estimates, but that it had been generally supposed that large differences could not be accurately so determined, and that the general idea had been that, as soon as photometry came generally into use, and so-called measurement took the place of estimation, a much more accurate scale of magnitudes, depending upon a true geometric light-ratio, would at once take the place of the old, the latter becoming obsolete, Mr. Chandler took for his text the general statement that instrumental photometry had thus far proved a failure; that is, it had not developed a more uniform scale of magnitudes than Argelander's, nor had the accuracy of individual determinations been increased, but they were, on the contrary, far more uncertain than the old differential naked-eye estimates. These statements he proceeded to back up with a convincing array of well-digested results, of which we can only give the briefest summary: 1o. For stars of Argelander's scale between magnitudes 2 and 6, the photometric catalogues of Seidel, Peirce, Wolf, Pickering, and Pritchard differed among themselves as much (or more) in their measures of what Argelander called a difference of one magnitude, as they did in their measures of his successive magnitudes. 2°. Their average values of the logarithm of the light-ratio (we will call it simply light-ratio hereafter, for brevity) for one of Argelander's magnitudes between 2 and 6, ranged between .30 and .38, about .35 for the mean of all the abovementioned catalogues. 3°. Between magnitudes 6 and 9 of Argelander, the catalogues of Rosén and Ceraski averaged about .35 for the light-ratio, while Pickering's late results with his large meridian-photometer gave (between magnitudes 6 and 8.5).48 instead of .35 for this ratio. 4°. To show the discrepancies in another way, assume a common light-ratio of .35 for all the photometers, and that their scales agree at magnitude 6. Then, for stars of the second magnitude, they will differ by 0.8 of a magnitude. That is, at a distance of four magnitudes away from where they agree, one photometer will say that the same star is twice as bright as another will. 5°. To test the uniformity of the different scales, all were referred to the average scale of all the photometers, and it was

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shown that Argelander's scale in the Durchmusterung' was just as close to this as that of any single one of the photometers. 6°. Coming to accidental errors, Mr. Chandler showed that, from a full discussion of the naked-eye estimates of Gould, Sawyer, and himself, the probable error of a single estimate was a little over +.06 of a magnitude when the stars were at considerable distances from each other, and about +.05 of a magnitude when near; while the probable error of a single measure in the Harvard photometry' was .17 of a magnitude, and in the Uranometria Oxoniensis' about ±.10 of a magnitude, thus showing that the eye-estimates were from two to three times as accurate as the photometric. 70. Discussing the cause of the large residuals in the Harvard photometry,' Mr. Chandler showed the strong probability of wrong identification of stars in many cases, citing one case where no bright star existed in or near the place called for by the observing-list, on account of a misprint in the Durchmusterung,' and yet some neighboring star was observed on several nights for it. 8°. Also the method of applying a correction for the mean value of the atmospheric absorption was very questionable, since overwhelming evidence pointed to an enormous difference in this absorption from night to night. 9°. The author pointed out that we must obtain better results from photometers if we ever expect to use their results for the detection or measurement of variable stars, since several variables have been detected, and their periods and light-curves well determined, by careful eye-estimates, whose whole range of brightness is no greater, or even less than, the range of error in the photometric observations upon a single star with the meridian photometer.

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In a discussion of a paper by Mr. Barnard upon 'Telescopic observations of meteor-trains,' Professor Newton pointed out that the study of their drift was the only method we have of studying the upper currents of our atmosphere, except such rare catastrophes as the Krakatoa explosion.

The closing paper was by Mr. Chandler, 'On the use of the zenith-telescope for latitude.'

PROCEEDINGS OF THE SECTION OF BIOLOGY.

THE regular work of the biological section began on Thursday, and a partial classification of the papers into botanical and zoölogical added considerably to the interest and convenience of those present. Some have proposed a divison of the section of biology into botanical and zoological sections, but this, with a small meeting, seems hardly desirable, as there are apt to be only enough papers to occupy the time.

Among the first of the botanical papers was one by Prof. W. J. Beal, giving a comparison between the hygroscopic cells of grasses and sedges. In both grasses and sedges, as has long been known, there are one or more longitudinal rows of cells on each leaf, the function of which is to fold or close the blade in times of drought, and thus prevent too rapid evaporation of moisture from the surface. These rows of cells, as well as the cells themselves, vary in shape, size, and distribution in the different genera and species, and may have some value in the discrimination of critical species. The most interesting point brought out was, that many parallels exist between the genera of grasses and sedges in the arrangement of these hygroscopic, or, - as Professor Beal chooses to term them, bulliform cells.

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The paper of Messrs. J. M. Coulter and J. N. Rose, giving a synopsis of the North American pines, based on leaf-structure, had some points in common with the one just mentioned, and was of especial value from a systematic stand-point, from the fact that any species in this somewhat difficult group can at once be distinguished by the peculiarities of its minute leaf-structure; and the results of the author's observations are shown to be worthy of attention from the fact that a classification based on these characters is, in its broader features, closely like that of the late Dr. Engelmann, which, as is well known, took into consideration the whole tree.

The relations of germs to disease naturally occupied a prominent place in the proceedings of the section, and the presence of over half a dozen investigators in this line made the discussions interesting. Dr. D. E. Salmon read two papers bearing on the causes of immunity from a second attact of germ diseases. There are three possible explanations: 19, something is deposited in the body during the attack which is unfavorable to the germ; 2°, something has been withdrawn which is necessary to its development; 3o, the tissues have acquired such a tolerance for the germ or for an accompanying poison that they are no longer affected by it. Dr. Salmon favored the last view, and gave details of a large number of experiments to substantiate his opinion. He said that Metchinkoff's phagocyte theory was not wholly satisfactory, and that large doses of the germs were more powerful than small ones. He attributed their action to a poison which was a result of their growth, and thought that a large dose had a greater effect because the poisons benumbed or killed the cells, thus giving the bacteria a better chance to grow and to thus produce more poison.

Dr. Joseph Jastrow gave an account of some

physiological observations on ants, in which he was able, by simple but ingenious means, to study the rate of walk of these insects, and stated that his results, so far as they went, confirmed the opinions of others that the smaller the animal the more rapid the step, and also the more quickly fatigue was produced. Dr. Jastrow also had some observations on the dreams of the blind, taken mostly from persons who had lost the sense of sight before the age of five. In these cases the dreams were all in terms of hearing. In the case of Laura Bridgeman, the dreams were apparently based on touch. In persons who become blind between five and seven, sight terms played an important part in dreams. The relation of these facts to the development of the sight centres was pointed out.

A short paper by S. H. Gage and Seth E. Meek, on the lampreys of Cayuga Lake, stated that the large lamprey, heretofore regarded as sub-specifically distinct, was identical with the well-known sea-lamprey of the Atlantic coast, the characters separating it being of a sexual nature and assumed at the breeding season. The existence of a second species in Cayuga Lake, hitherto not known east of Indiana, was mentioned. The authors described the method of nest-building, stating that the lampreys seek out a spot in the still water above the ripples, and then, by means of their sucking mouths, remove the stones until a nest from four to eight inches deep is made. In the sand in the bottom of this nest the eggs are laid. The time of oviposition was from June 9 to July 6 during the present year. The pile of gravel thrown up in making the excavation is not the nest, but later it is found to be occupied by the ammocoete larva.

The most important feature of Dr. Kingsley's account of the embryology of the shrimp (Crangon) related to the development of the compound eye. Locy was the only previous observer of the early stages of the eye of anthropods, and Dr. Kingsley's observations confirmed his results as well as going more into detail.

Dr. C. S. Minot, in his paper on the segmentation of the vertebrate ovum, reduced all types of segmentation to a common basis, and clearly pointed out the homologies. The most important point was that which showed that the majority of authors had confused the germ-layers in the mammalian ovum, and have termed the entoderm, ectoderm, and vice versa. On Dr. Minot's showing, the difficulties encountered in mammalian embryology are largely those of misconception and misinterpretation.

Dr. Merriam, after mentioning the fact that bats might be divided into tree-dwelling and cave

dwelling forms, presented evidence, of a negative character, which goes to show that the treeinhabiting bats migrate. No woodsmen have found bats in hollow trees in winter, and there is no evidence that any forms hibernate. In a second paper the same gentleman gave an outline of the work being done in the department of agriculture, on economic ornithology and mammalogy, in which he pointed out, in most vigorous language, the immense damage done the agricultural interests by the bobolinks and English sparrows. One South Carolina planter with rice-fields of twelve hundred acres employed each year a hundred persons to kill the birds, at a total expense for ammunition, etc., of $4,500.

Among the papers read were the following : 'Culture experiments showing accidental relations between Gymnosporangia and Rolstelia,' by Dr. W. G. Farlow; Insect diseases,' by Prof. S. A. Forbes; Areas of form and color perception of the human retina,' by Prof. J. H. Pillsbury; 'Development of the human chorion,' by Dr. C. S. Minot; and, The auditory bones in the lower vertebrates,' by Prof. E. D. Cope.

MUSK is an animal substance, obtained from an abdominal sac of the male of the Moschus moschatus, a small hornless deer inhabiting the higher mountains of central Asia, ranging from Thibet to China, and into Asiatic Russia. The contents of the musk-sac are a solid, brownish, granulated, ovoid mass, exceedingly strong and tenacious in odor, and varying in size from that of a walnut to that of a hen's egg. There are four varieties of musk, viz.: Tonquin, from China, regarded as the best, and which is looked upon as the most recherché; Yunnan, from the frontiers of Indo-China; Assam, or Bengalee; and, least valued of all, Kabartin, from Tartary and Siberia. Musk is very expensive, the price at present ranging from eight to twenty dollars per ounce, in the pods or bags, according to grade. This high price is the cause of much adulteration, in this country as well as at the place of production; so that there is very little in the market that can be considered pure. principal adulterants are lead, iron, coagulated blood, leather, stones, and even paper and rags. The adulterant is inserted in the bag, and the opening closed in such a manner as to defy detection. About five hundred pounds of musk are used annually in the United States, of which ninety-five per cent goes into toilet soaps and perfumery, the rest being used for medicinal purposes.

The

- PROF. JOHN DICKINSON, a brother of Miss Anna Dickinson, has accepted the chair of geology and mineralogy in the University of Southern California at Los Angeles.

FRIDAY, SEPTEMBER 10, 1886.

COMMENT AND CRITICISM.

THE SMITHSONIAN REPORT for 1885, which we may hope will be issued with less delay than its predecessors have been, will contain an account of the progress in astronomy for that year, by Mr. William C. Winlock of Washington, which has already appeared with sufficient promptness as a separatum. Mr. Winlock forestalls at once any criticism we might otherwise like to make by pleading the brief time necessarily available as an excuse for any shortcomings that may be found, and remarks that his record is intended primarily for the large and increasing class of those who have a general rather than a special interest in the progress of astronomy, while it may be of use to the professional astronomer also, as a convenient collection of reviews and notes. Abstracts of the most important papers are given, while other papers appear by title only, and free use has been made of reviews in such periodicals as Science, The athenaeum, The observatory, and Bulletin astronomique. Comets, a specialty of Mr. Winlock's, are very fully and accurately dealt with; and his method of indicating the names of all these objects, now become so numerous with every year, is an important advance.

Independently of the excellences or shortcomings of the present work, we think the question may fairly be raised whether these annual reports are worthy of continuance or not. They are, through no fault of the author, rather tame reading for those having only a general interest in astronomy, being largely a mere recital of the new facts of the year's finding out, with no connecting-link to the astronomy of the past. To be sure, the developments of astronomy within a twelvemonth are rarely sufficiently far-reaching for even the practical astronomer to keep in mind the precise relations of past and present research. Again, if these reports are prepared for the convenience of the professional astronomer, it may well be doubted whether they are worth what they cost the astronomer who undertakes to prepare them; for the work is no ap

No. 188.-1886.

proach, in point of serviceableness, to a complete bibliography for the year, such, in fact, as Mr. Winlock himself broaches the preparation of, perhaps through the co-operation of astronomers. If this is found practicable, then the editor of the Smithsonian report might well confine himself to the presentation of a quinquennial history of astronomical progress, to be prepared by the ablest astronomer who would undertake the task, and who would be expected to indicate clearly the bearings of recent research upon that of previous years, and weld the scattering links into a continuous chain. It is easy to see that the work executed in this manner would have an important bearing upon the diffusion of knowledge among men,' which, in its present form, it does not possess.

JUDGING BY THE SCIENTIFIC AGITATION which has shaken England for so many years, one would hardly credit the statement made by Sir John Lubbock in his address at the unveiling of the statue of the founder of the Mason science college, that, in 54 of 240 endowed schools for boys which have reported, no science whatever is taught; in 50, one hour is devoted to it per week; in 76, less than three hours; while only 56 devoted as many as six hours to it. According to the report of the Technical commission last year, there were only three schools in Great Britain in which science is fully and adequately taught. In urging the benefits of science, Sir John Lubbock says, "In the first place, science adds immensely to the interest and happiness of life. It is altogether a mistake to regard science as dry or prosaic. The technical works, descriptions of species, etc., bear the same relations to science as dictionaries to literature. ... Occasionally, indeed, it may destroy some poetical myth of antiquity, such as the ancient Hindoo explanation of rivers, that Indra dug out their beds with his thunderbolts, and sent them forth by long continuous paths.' But the real causes of natural phenomena are far more striking, and contain more real poetry, than those which have occurred to the untrained imagination of mankind."

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DR. THOMAS TAYLOR'S MICROSCOPIC METHOD for detecting the adulteration of butter with foreign

fats seems destined to assume as many shapes as Proteus. At first the globose forms, obtained by the boiling and subsequent slow cooling of butter, and exhibiting the Saint Andrew's cross under polarized light, were brought prominently forward as distinguishing marks of pure butter. Prof. H. H. Weber, however, upon testing the method as described by Dr. Taylor, found, that, although the so-called butter crystals could be readily prepared from butter, they could be as readily prepared from beef-fat, or mixtures of beef-fat and lard, under like conditions. The necessary conditions are, the slow cooling of the melted fat in the presence of minute solid particles about which the fat may crystallize, the so-called butter crystals' being aggregations of minute crystals radiating from a centre. In the test as described by Dr. Taylor, the butter is boiled for one minute, and then slowly cooled. During the boiling, some of the water of the butter evaporates, and a corresponding portion of its salt solidifies, and the minute crystals thus formed serve as centres of crystallization for the fat during the subsequent cooling.

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After the publication of these results, the 'butter crystal' and its Saint Andrew's cross were relegated to a subordinate position, and in several publications Dr. Taylor insisted that his most important test had been neglected, viz., the appearance of the unboiled material under polarized light with a selenite plate. According to Dr. Taylor, butter shows a uniform tint, while lard and tallow show prismatic colors. Here, again, however, he has been pursued by Professor Weber, who shows that either butter-fat or lard or tallow, when cooled quickly, will show a uniform tint, while if cooled slowly, so as to admit of the formation of larger crystals, prismatic tints are shown by both. Since imitation butter is cooled rapidly when made, and since both genuine and imitation butter are liable to undergo sufficient changes of temperature after manufacture to allow of a partial re-crystallization, the test is plainly fallacious. Apparently, Dr. Taylor prepared his annual report with these results in mind, for there, and in his paper before the annual meeting of the American society of microscopists at Chautauqua, Aug. 10-16, he gives his method a still different exposition.

Dr. Taylor's first step is now to search for fat crystals in the test sample by plain transmitted

light. By the application of polarized light, 'amorphous crystals,' whatever these may be, may be detected. To determine whether these 'amorphous crystals' are of beef-fat or lard, the sample is boiled and slowly cooled, as already described, and mounted in oil. Under these conditions, he now finds, in accordance with Professor Weber, that butter, lard, and beef-fat all give globular crystalline bodies which (apparently with the exception of lard) show the Saint Andrew's cross. These bodies are to be distinguished by their forms, lard giving a stellar form, butter the well-known 'butter crystals,' and beef-fat a stellar form with biserrated spines. Dr. Taylor has also discovered the noteworthy fact that Tennessee butter of a certain grade yields globules which are flattened or indented on one side! The above account of Dr. Taylor's method, as at present described by him, is drawn mainly from his last annual report to the commissioner of agriculture, — his Chautauqua paper, to judge from the published abstract, having been chiefly a criticism on Professor Weber's experiments. We shall endeavor to keep our readers informed of the changes which the method undergoes in the future.

THE EARTHQUAKE OF AUG. 31, 1886. THE accompanying map has been hastily compiled from the great mass of conflicting data from all sources now available, and probably gives a fair general idea of the origin of the shock, the limits of the area disturbed, and the intensity at many points within this area (plotted on the American scale of intensity, 1 to 5). It will be readily appreciated by every one that in this preliminary report all that is or can be arrived at is to give a general outline, as determined by the most probable evidence at hand, to serve as a good working hypothesis: to attempt any thing further at present would be to make a mere pretence at accuracy.

A line of weakness in the earth's crust extends from Troy, N. Y., south-westward, along the line of tidewater, past Baltimore, Washington, and Richmond, losing itself in a broad flexure south of Raleigh. The cause of the shock seems to have been a renewed faulting or displacement along the line where it crosses the Carolinas. This severe shock appears to have had its origin along this line in central North Carolina and eastern South Carolina, at 9.49 P.M. (75th meridian time), Aug. 31. It was not without warning. For a long time slight shocks have been occasionally felt in North Carolina, and only a few

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