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and in the blood was there shown. The mechanism of the function had been announced before Schiff's experiments appeared. “M. Schiff says himself that he agrees with me; but he thinks that he has more accurately distinguished and located microscopically the hepatic starch, and so has proved my views better than I have myself. If this be so, I cannot but be satisfied ; but I see not how this gives him any claim to priority.”
(54.) On the 30th of May, Rouger communicated another paper to the Academy, * on the amorphous amylaceous matter contained in the vertebrate and invertebrate fætal tissues. This substance—for which he proposes the name Zoamylin-is not granular, but consists of a plasma holding in suspension fatty or nitrogenous granulations. Moreover, ossifiable cartilages must be added to the embryonic tissues containing amylaceous matter ; though this is not found in the substance of the cartilage, but only in the cells, which in a fætal lamb 11 to 2 months old, are colored rose-violet with iodine. With this amylaceous plasma too, the epithelial cells of the digestive, respiratory and genito-urinary passages, of the interior of the eyelids and even of the cornea, are filled. With young ruminant embryos, the cartilaginous, muscular, and epithelial elements of which contain zoamylin, no trace of glycogenic cellules appears on the surface of the amnion. When these are present their mode of development, their form, constitution and general appearance are precisely like those of the cellules of the horny layer of the epidermis ; and 'hence prove the amnion to be an extension simply of the skin. The presence of amylaceous matter in the amnion and placenta, therefore, is not a special case, since all fæetal tissues contained it. No new hepatic organ exists, nor has the placenta any new function. The presence of this substance is the evidence, not of a new function in an organ, but of a new property of tissues. The production of sugar is not the object but the consequence of the existence of zoamylin in the organism. The sugar accumulated by the urinary secretion in the allantoic and amniotic fluids, is a result of the destruction of the fætal zoamylin, precisely as urea is produced by the metamorphosis of proteic bodies. (55, 56.) Already given as paragraphs (43) and (44).
* C. R., xlviii, 1018.
(To be concluded.)
ART. XXIV.-A New Meteoric Iron—"The Wisconsin Me
teorites"-with some remarks on the Widmannstätian Figures ; by J. LAWRENCE SMITH, Louisville, Ky.
THESE meteorites were first brought to my notice by Mr. I. A. Lapham, of Wisconsin, and his attention was called to them by Mr. C. Daflinger, Secretary of the German Nat. Hist. Society of Wisconsin. 'They were discovered in the town of Trenton, Washington county, Wisconsin, and I have called them the “ Wisconsin meteorites. Up to the present time, fragments have been found, indicating that these meteorites were of the same fall and separated at no great elevation. They were found within a space of ten or twelve square yards, very near the north line of the 40 acre lot of Louis Korb, in latitude 43° 22' N., and longitude 88° 8' west from Greenwich, and about 30 miles north west of Milwaukee.
They were so near the surface as to be turned up with the plough; they weigh 60, 16, 10, and 8 pounds respectively, and present the usual pitted and irregulur surfaces.
The largest of the meteorites in i s extreme dimensions, is 14 inches long, 8 inches wide, and 4 inches thick, weighing 62 pounds. Its specific gravity is 7.82, and composition, Iron
0:14 Copper .
minute quantity Insoluble residue
0.45 A polished surface when etched gives well marked Widmannstättian figures. There is something, however, peculiar about the markings on this iron, which is doubtless common to other irons, but which has heretofore escaped my observation, and I cannot discover, in a hasty investigation, that it has been noticed by others. My attention was called to this peculiarity by Mr. Lapham, on a slice of the meteorite I sent him etched; should these markings be entitled to a separate notice, I propose calling them Laphamite markings. The little drawing accompanying this, which is on a somewhat exaggerated scale, will show what they are.
The Widmannstättian figures are a, bright metallic, with con
vex ends and sides ; b c, of a darker color, are the other markings, usually smaller and with the sides and ends concave. The material of which these dark figures are composed seems to have enveloped the lighter colored portion, which serves to make the dark lines so beautifully conspicuous. A good pocket glass will show that the darker figures are striated, with lines at right angles to the bounding surfaces. When the figure is nearly square, the lines extend from each of the four sides, but when much elongated, as at c, they are parallel with the longer sides. Often these lines do not reach the middle of the figure, where only a confused crystallization can be detected. In the interior of the elongated figures, the lines are quite irregular, often running together, and showing a striking resemblance to woody fibre. The nature of these markings may be easily understood. They indicate the axes of minute columnar crystals, which tend to assume a position at right angles to the surface of cooling.
These markings may have been observed by others; and as soon as the subject can be examined on other irons, a better conclusion can be formed.
I. PHYSICS AND CHEMISTRY.
1. On the wave lengths of the metallic rays.-THALÉN has published an extended memoir on the wave lengths of the spectral lines of the elements. The author's work does not present any new measurements, but is based upon those made by Angström, which had already been employed for the purpose of interpolation by the writer of these notices. The method of proceeding was however new. Each luminous ray, the wave length of which was to be measured, was in the first place entered either upon Kirchhoff's chart, which extends from A to G, or upon a new chart by Angström and Thalén, extending from G to H. These rays were then transferred to the normal plates of the spectrum furnished by Angström, and finally were entered upon the charts published with Thalén's memoir, each being placed according to its wave length. In some cases the graphical method was employed. The description of the process employed in determining the wave lengths is by no means clear. The spectroscope used was provided with large telescopes, and with a prism of bisulphid of carbon with a refracting angle of 60°. The number of elements examined amounted to 45; of these 23 were in the metallic state, the others being in the form of chlorids. One important result obtained by the author is the proof that the sun's
atmosphere contains titanium. The following elements had, so far as the writer knows, not before been examined with the spectroscope; glucinuin, zirconium, erbium, yttrium, thorium, uranium, titanium, tungsten, molybdenum, and vanadium. Appended to Thalén's memoir is a chart upon which the spectra of the different elements are entered upon the plan first employed by Mr. Huggins, so that all the spectra are upon one sheet with the normal spectrum at the top. It must be borne in mind, however, that the lines upon Thalén's map are entered according to their wave lengths and not upon an arbitrary scale. The memoir contains, also, a complete table of the wave lengths of all the lines of the elements examined. With respect to the numerical values of these wave lengths the writer will only remark that they differ widely from those determined by himself in the discussion of Mr. Huggins's scale, in the present number of this Journal.- Nova Acta Reg. Soc. Scient. Upsaliensis. Series tertia, vol. vi, fasc. 11, 1868.
2. On spectral analysis.-In another memoir on spectral analysis, published in 1866, but which has just reached us, Thalén has given what amounts to a complete history of, and treatise on, the subject. The memoir contains what has long been wanted, maps of the spectral lines of the elements as seen with a single prism of bisulphid of carbon with a refracting angle of 60°. These maps give the principal lines for each element. They are all upon a single sheet, upon Mr. Huggins's plan, with the solar spectrum at the top for comparison, and with a scale of millimeters. A prism of the bisulphid of 60° has become a sort of normal or standard, easily and cheaply obtained, and extremely convenient for common use and reference. Thalén's chart is therefore a most acceptable addition to our resources, and will, we hope, be published separately.-Upsala Universitets. Arsskrift.
3. On a normal spectrum of the Sun.-FIZEAU has presented to the Academy of Sciences, on behalf of the author, A. J. Angström, a new atlas of the solar spectrum. This atlas contains six detailed charts, representing different parts of the solar spectrum, drawn from new observations upon which their author has spent five years. The map contains also a description of the violet portion of the spectrum between G and H, which was wanting in the chart of Kirchhoff and Hofmann. Upon these charts the lines are entered simply according to their wave lengths, a method which Fizeau attributes to Angström. That the new charts will prove of the greatest value and interest cannot be doubted.
With respect to the originality claimed for their construction, it may be remarked that the method was first proposed by Billet, (Traité d'Optique, vol. I, p. 47,) and that the first extended chart constructed in accordance with it, was presented by the writer of these notices to the National Academy of Sciences, Aug. 7th, 1866. This chart contained 87 lines.-(This Journal, vol. xliii, Jan. 1867.) Comptes Rendus, lxvii, 946.
4. On the red protuberances from the surface of the sun.-In verifying the observations of Lockyer and Janssen upon the light
of the solar protuberances, Secchi has made some new observations of interest. One protuberance was observed perfectly detached from the sun's border, the ray C being prolonged at both ends by the continuation of the dark
At another point the ray Cappeared to touch the edge of the sun's disc. Another protuberance appeared and disappeared at intervals. One fact, showing the abundant presence of hydrogen, is that the ray C disappears almost all round the sun, at the same time that the ray F becomes much feebler.
Lockyer finds that the protuberances are simply local accumulations of a gaseous envelope, which completely surrounds the sun. The thickness of this envelope is about 5000 miles, (8000 kilometers,) and it is wonderfully regular in its entire contour, its distance from the sun being sensibly equal at the pole and at the equator.
Secchi gives the thickness of the envelope as 15 seconds in its thinnest part, and thinks that it may be at least 30 seconds on the average. The yellow line near D, as remarked by other observers, is not a hydrogen line, and does not correspond to any dark line in the spectrum. On applying the spectroscope to the examination of Jupiter, Secchi found that the dark band in the red does not coincide with the band C, which we see in our atmosphere. The same astronomer has had opportunities of studying the spectra of several meteors.
One of them exhibited a discontinuous spectrum, the principal luminous rays being red, yellow, green and blue, and very brilliant, In the cases of two other very brilliant meteors, the magnesium ray (6?) was superb.-Secchi in Comptes Rendus, lxvii, 1018, 937, 1123. Lockyer in the same, lxvii, 949.
5. Further observations on the spectra of some of the stars and nebule, with an attempt to determine there from whether these bodies are moving toward or from the earth, also observations on the spectra of the sun and of comet II, 1868.—Under the above title Mr. Huggins has brought together a number of interesting and important contributions to astronomical physics and chemistry. In an introduction to the memoir the author discusses the proposition first stated by Doppler in 1841, that the color and intensity of an impression of light, and the pitch and strength of a sound will be altered by a motion of the source of light or sound, or by a motion of the observer, toward or from each other. The introduction contains a concise and clear statement of the theory of the change in refrangibility of light produced by the motion of the observer, or of the luminous body, contributed by Mr. S. Clerk Maxwell. The apparatus employed by Mr. Huggins consisted of an equatorial by Alvan Clark, with an eight inch objective, and a peculiarly constructed spectroscope, the dispersive power of which was equivalent to that of about six flint prisms of 60° and one of 45°. It is only by means of an instrument having a very high dispersive power, that the small difference in refrangibility produced by a small change in the wave length can be measured. With this spectroscope observations were made of the great neb