believes, necessarily indicate the existence of a nucleo-proteid in . them, for Dr. Elliott has found that they digest in artificial gastric juice, leaving no residue, which would not be the case were a nucleo-compound present.

The outer portions of the rods and cones in Menobranchus and Diemyctylus are rich in organic compounds of phosphorus. It is more abundant in the rods than in the cones, and it is not due to lecithin, for the retinæ used were freed from the latter, nor is it owing to the presence of inorganic compounds of phosphorus, for the reaction is not obtainable during the first twenty minutes after placing the organs in the nitric-molybdate solution, while it is a progressive one up to the sixth hour. The chromatin of the nuclei of all the layers of the organ also gives the reaction.

The chromatophore in Spirogyra gives a weak phospho-molybdate reaction, and it appears to be due to the presence of an organic compound of phosphorus. A more marked reaction, however, is usually found in the pyrenoids in the same genus, and also in those of Edogonium, Cladophora, and Conferva. In fresh specimens of Spirogyra, taken during daylight and put into the nitric-molybdate reagent, the pyrenoids appeared to give a stronger reaction than those of specimens taken at ten o'clock at night. The reaction develops slowly.

A diffuse reaction for phosphorus, slow in developing, was obtained in the cytoplasm of Saccharomyces Ludwigii. In apparently normal cells this may be the only reaction which will be obtained, but in cells cultivated in the sap of the iron-wood tree a spherical body occurs, at first sight like a nucleus, but frequently homogeneous, which after about ten hours' treatment with the nitric-molybdate reagent gives a reaction for phosphorus which may be very marked. This body is in no sense a nucleus,* nor does the phospho-molybdate reaction reveal any structure that corresponds to the latter. The fact that the "masked " iron in these cells has a distribution parallel to that of the organic phosphorus, also points distinctly to the absence of a nucleus.

In Cyanophyceae the "central body" always gives evidence of the presence of organic phosphorus compounds. A stronger reaction for phosphorus was obtained in the iron-holding, chromatin-like granules which are to be found in the central body, or on its periphery, in Tolypothrix and Oscillaria. The "cyanophycin" granules, on the other hand, have not given any evidence of the presence of organic phosphorus except in some few filaments of a preparation of Oscillaria tenuis, in which case a marked reaction was developed in about an hour.

I have discussed the nature of this body, 'Quart. Journ. Micr. Sci.,' vol. 38, p. 246.

FALMOUTH MAGNETIC OBSERVATORY.

IMPORTANT NOTE.

The observations made at this Observatory during 1897 have not been printed at their usual place in the 'Proceedings,' as the Dip observations for the period between October 8, 1895, and June 5, 1897, inclusive, have been found to be affected with certain errors.

OBITUARY NOTICES OF FELLOWS DECEASED.

Dr. HUBERT A. NEWTON, Professor of Mathematics in Yale University, whose death occurred on the 12th of August, 1896, was born in 1830, on the 19th of March, at Sherburne, in the State of New York. Both his parents were descended from ancestors who were among the first British settlers in Connecticut. His father built the

Buffalo section of the Erie Canal, and it is recorded of his mother, whose maiden name was Butler, that she was remarkable for her mathematical attainments. He was one of ten children--seven sons and three daughters.

At school the lad showed the aptitude for mathematics, and especially for geometry, which distinguished him throughout his life. He entered Yale University at the age of 16, and graduated with the highest mathematical honours in 1850. After his graduation he continued for two and a half years more to devote himself to the study of advanced mathematics, at the expiration of which time he was, in 1853, appointed mathematical tutor in his university. Two years later, at the unusually early age of 25, he was elected to the full professorship, which he held through the rest of his life. In 1859 he married a daughter of the Rev. Joseph C. Stiles, who survived her husband only three months, leaving two daughters.

Professor Newton's life was one of great industry. He was Associate Editor of the American Journal of Science' for twenty-seven years, was a member and afterwards President of the Publishing Committee of the Connecticut Academy of Arts and Sciences, and, in addition to a long list of original memoirs, wrote articles for various cyclopædias, among others for the Encyclopædia Britannica.' He took an active part in promoting the introduction of metric measures into America, and on the Board of Management of the Yale Observatory, which owed its existence largely to the efforts and personal sacrifices of Professor Newton, and of which he was for a long time Secretary and for two years Director. He even took a part in municipal affairs, and it is characteristic of the esteem in which he was held, that it is recorded of him that he was elected alderman in a ward in which the prevailing politics were in opposition to his own. In 1875 he presided over the Mathematical Section of the American Association for the Advancement of Science, and in 1885 was President of the Association. At an early period he received the honorary degree of LL.D. from Michigan University, and in 1888 was

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awarded the Smith Gold Medal of the American National Academy of Sciences, in recognition of his original work. In this country he was elected a Foreign Member of the Royal Society, of the Royal Astronomical Society, and of the Royal Society of Edinburgh. The first of his papers seems to have been published in 1857, and the last, "On the Relation of the Plane of Jupiter's Orbit to the Mean Plane of 401 Minor Planets," in 1895. Between these dates he published a long series of papers-usually from two to four each year-covering a variety of subjects in mathematics, insurances, and especially in that branch of astronomy which relates to meteors and comets. These intimately connected phenomena early fixed his attention. His first paper in reference to them was published in 1860, and a continuous succession, nearly fifty in all, have been the result of his studies in this department of astronomy, and have contributed largely to the immense advance which the astronomy of meteors has made within the last forty years.

Two memoirs may be selected to illustrate how much modern science owes to Professor Newton's industry and clear insight. The first of these is his great memoir entitled "The Original Accounts of the Displays in former times of the November Star-shower: together with a Determination of the length of its Cycle, its Annual Period, and the probable Orbit of the Group of Bodies round the Sun." This memoir is published in the 'American Journal of Science' ('Silliman's Journal'), vols. 37 and 38 (1864). In it Professor Newton makes use of the collections of ancient records of star-showers which had been brought together chiefly by the great industry of French antiquarians and French astronomers. From these records Professor Newton traces out all which refer to former visits to the earth of that great swarm of small bodies which are now known as Leonids, but which, when first observed, radiated from the constellation Cancer. In each case he cites the actual words of the original records, of which there are usually several referring to each shower; and by a careful scrutiny of these he is able to fix, in many instances with certainty, in others with more or less probability, the actual date on which each shower occurred, and even in some cases the hours during which it lasted. He thus discovered that we possess records of thirteen showers of these meteors, of which the earliest was in A.D. 902, and the last (at the time when he wrote this memoir) was in 1833. To these we have now to add the two great displays witnessed from Europe in 1866, and from America in 1867.

By this careful scrutiny Professor Newton discovered several important facts-that the main swarm returns to the earth at intervals of 33.25 years; that on each return the earth encounters the dense part of the swarm in two consecutive years; that the date of the

12, old style, which was the date in A.D. 902, to November 12, new style, which was the date in 1833; and finally that the meteoric orbit, whatever it is, is but little inclined to the ecliptic, and that the motion of the meteors where they enter the earth's atmosphere is nearly perpendicular to the direction of the sun.

Such being the facts, he proceeds to determine what inferences may be drawn from them. From the dates of the showers he ascertained that the node of the meteoric orbit-the point of its intersection with the earth's orbit-has been since A.D. 902 advancing in longitude nearly uniformly and at the average rate of 1·711' annually. Allowing for the precession of the equinox, this is equivalent to an advance of 29′ in 33 years, measured from a fixed point. This motion is accordingly direct, and Professor Newton infers from this and from dynamical considerations that the motion of the meteors in their orbit must be retrograde. He next considers whether the meteoric orbit is wholly or only partly occupied by the dense swarm of meteors. He first examines the hypothesis of an elliptic orbit along which the meteors are distributed uniformly, and which suffers such perturbations that it shifts about so as periodically to intersect the earth's orbit three times in a century. He finds that this hypothesis must be rejected, because it involves an apsidal motion so rapid as would require perturbing forces of an intensity which we can satisfy ourselves do not exist. Accordingly the meteors, leaving out of account the sporadic meteors which have got separated from the main swarm, occupy only a portion of their orbit. He next inquires what further can, be learned about an orbit of which the main swarm of meteors occupies only a portion; and he made the important discovery that only five orbits are compatible with the observed return of the swarm to the earth at intervals of 33 years. One of these five, accordingly, must be the true orbit. Professor Newton determined the periodic times in these orbits, and thus ascertained the axis major of each. All that was then wanting to fix the precise form and position of each of the five orbits was a sufficiently accurate determination of the "radiant point," i.e., of that direction from which the meteors are seen to enter our atmosphere. On account of Professor Newton's representations, efforts were made by astronomers to make this observation with the utmost care during the great meteoric showers of 1866 and 1867. This direction, when corrected for the deflection of the meteors by the earth's attraction, furnishes the position in space of one tangent to the orbit. Knowing then the focus, the axis major, and the position and point of contact of one tangent of each of the five orbits, its exact form and situation in space can be ascertained. Thus the five orbits become fully known; and the next step was to determine which of them is the