to Zoology. Intended for the College and the Parlor. Elements of Ornithology. With Plates. 1 vol. 12mo. Boston. 1847.

History of the Town of Medford, Middlesex County, Massachu setts, from its First Settlement in 1630 to the Present Time, 1855. By Charles Brooks. 1 vol. 8vo. Boston. 1855.

The Commissioners of the Public Library.

Proceedings on the Occasion of Laying the Corner-Stone of the Public Library of the City of Boston. 1 vol. 8vo. Boston. S. L. Abbot, M. D.

1855.

Report of the Board of Trustees of the Massachusetts General Hospital. Presented to the Corporation at their Annual Meeting, January 23, 1856. 8vo pamph. Boston. 1856.

Royal Academy of Sciences, Stockholm.

Ofversigt af Kongl. Vetenskaps-Akademiens FörhandlingarTionde Argången, 1853; Elfte Årgången, 1854. 2 vols. 8vo. Stockholm.

1854-55.

The Academy met at the house of the Hon. John C. Gray. The President in the chair.

The Corresponding Secretary read a letter from Dr. J. P. Kirtland of Cleveland, Ohio, accepting Fellowship.

Mr. G. P. Bond presented a paper "On the Use of Equivalent Factors in the Method of Least Squares," which, on motion of Professor Lovering, was referred to the Committee of Publication.

Professor Eustis exhibited an apparatus illustrating a peculiar case of warped surfaces. The apparatus consisted of two planes at equal distances from each other, having upon their contiguous surfaces, and opposite to each other, figures of an ellipse. From the whole circumference of each of these ellipses cords were tightly drawn obliquely across to a corresponding but opposite point in the other. The effect, on looking through an aperture in the middle of the apparatus, was a very peculiar series of curves, resulting from the crossing of so many straight lines.

At the request of Professor Horsford, Dr. Charles T. Jackson stated that, in his recent examinations of Cochituate water, he had found the Crustacea, to which the impurity of that water in 1855 was attributed by some, quite numerous. A month since the Cyclops were as abundant as at any time, except when the water was first introduced into the city. They always contain more or less oil, of various colors. Dr. J. had collected a teaspoonful of them, and observed, on boiling, that they became of a bright orange-red color. He could perceive no disagreeable odor or taste to the oil; but when the mouth was rinsed with water containing it, it left a peculiar stinging sensation in the throat, resembling what Professor Horsford and himself had noticed in tasting the water of the lake in situ. The oil was always found in these Crustacea.

Dr. A. A. Gould remarked, that other observers had stated to him that the Crustacea are far less numerous this year than last, and contain much less oil. The number is found, as then, to vary very much at different times and places. He doubted if oil was found in them at all times. It was his impression, also, that it had been but recently noticed. In the figures and descriptions of them by European observers, he believed no delineation or mention of its existence occurred. On the authority of Professor Jeffries Wyman, who had been recently studying those found in the wells of the College yard, Cambridge, he stated that there was abundance of oil in the bodies of the specimens from that locality.

Dr. Jackson mentioned that one European observer had recorded its existence, namely, Kölliker.

In reply to a question of Professor Horsford, whether the animals in question ever feed on anything but vegetable food, Dr. Gould said that the Crustacea in general are known to be carnivorous. He could not speak positively with reference to the microscopic species.

Dr. Pickering said that no Crustacean had ever been known to feed on vegetable matter.

Professor Lovering exhibited and explained Wheatstone's photometer.

Dr. A. A. Gould made some statements concerning the supposed ejection of living animals from the human stomach, where they had been believed to have resided for some time, but which, from their structure and habits, could not have lived under such conditions. He mentioned several instances, one that of a snake, supposed to have existed for months in a man's stomach, which on being opened was found to contain in its stomach another snake, of a different species, which it had swallowed; all tending to confirm the probability that all such stories are palpable fictions, or the offspring of honest delusion.

Four hundred and twenty-seventh meeting.

May 13, 1856. MONTHLY MEETING.

The Academy met at the house of the Hon. Nathan Appleton. The President in the chair.

The Corresponding Secretary read letters from Rear-Admiral W. H. Smyth, acknowledging the donation of the Academy's Memoirs, and from Die Königlich Sächsische Geselschaft der Wissenschaften, and the Lyceum of Natural History, New York, acknowledging the donation of the Proceedings of the Academy.

Referring to the statements concerning the Cochituate water at the preceding meeting, Dr. A. A. Hayes said, that, in a paper read by him last year, he had demonstrated that the impurity existing at that time was due to an animal origin, and he had seen no reason to change his view since.

Dr. John Bacon remarked, that he had noticed the oil-containing Crustacea during the past year, especially in the very cold months, when there was very little vegetable matter in the water. He had seen no reason to change his former opinion concerning them.

Dr. C. T. Jackson said, that, shortly after the Cochituate water was introduced into Boston, he had collected great numbers of the Crustacea, at a time when the water was very pure.

Dr. Bacon had pointed out to him the oil in their bodies, a year before there was any complaint of any bad taste in the Afterwards, when the water was quite impure, they were much less numerous, and as the water became purer their number increased.

Dr. C. Beck said, that

"he had for some time been occupied with an attempt to give an answer to the question in what age Petronius Arbiter, the author of the Satyricon, lived and wrote. After remarking that Petronius was the most important and interesting of the small number of Latin prose-writers of fiction, and after giving a brief account of the contents of the Satyricon, so far as it is still extant, he adverted to some of the facts in the external history of the book. He stated that, from several circumstances, it is probable that the portion now left is not more than one fifth, and may be not more than one tenth, of the whole work; and that this loss of four fifths, or nine tenths, was sustained between the thirteenth and fifteenth century, because John of Salisbury, a writer of the thirteenth century, quotes passages from Petronius which are not to be found in the first printed editions of 1470 and succeeding years. He related the discovery of the Tragurian fragment, in 1663, at Tragurium in Dalmatia, which, containing the description of the banquet of Trimalchio, and forming one of the most important portions of the work, repaired the loss previously sustained to a small extent only. After speaking of the discussion to which this discovery gave rise, and the speedy acknowledgment of the genuineness of the fragment, he adverted, in a few words, to the bold fraud of Nodot, in attempting to pass upon the learned world, as genuine, a manuscript which he pretended to have found in Belgrade, but only with partial and temporary success.

"He next spoke of the great diversity of opinion among scholars as to the age of Petronius, some placing him as early as the times of Augustus, others as late as those of Constantine; a diversity of opinion ranging, therefore, over a period of three hundred years. After stating that perhaps the majority of scholars, of the present as well as past ages, misled by the passage in the Annals of Tacitus, 16. 17 and following, in which is given the history of C. Petronius, a man of consular dignity, and, on account of his refined taste and skill in arranging and inventing new pleasures, for a time a great favorite of Nero,had adopted the hypothesis that this Petronius was the author of the

Satyricon, and that the communication mentioned in Tacitus as having been sent by Petronius to the Emperor Nero was the Satyricon; and after showing that this hypothesis, however plausible, is untenable, he adverted to some of the principal difficulties in satisfactorily answering the question concerning the age of Petronius. One is the absence of all external evidence; since the passage in Tacitus, which by some has been considered as external evidence, unquestionably does not refer to the author of the Satyricon.

"This being the case, internal evidence alone remains, and this is naturally divided into two kinds, the historical and linguistic. The former consists in allusions to persons, events, customs, and institutions, political as well as religious and social; the latter in peculiarities of language and style. The historical evidence leads, in Mr. Beck's opinion, to the conclusion that the work was written during the latter part of the reign of Augustus or the beginning of that of Tiberius, some time between the year 6 and 30 after Christ; and the evidence of language is not only compatible with that conclusion, but confirms it.

“After referring to the circumstance that one of the greatest literary excellences of the book, namely, the variety of styles occurring in the book, since, besides the language of the narrative, which is simple and elegant, each character introduced into the story is represented, and with remarkable skill too, as using such language as is suited to his age, social station, and degree of education, increased the difficulty of settling the question of the age of Petronius, he closed with the account given by Gellius of the word fruniscor, which is, in the Satyricon, put into the mouths of several individuals, as a specimen of the evidence of language having a bearing on the point in question."

Professor Jeffries Wyman gave an account of the peculiar structure of the organs of voice in the male Surinam toad.

Dr. A. A. Hayes exhibited a peculiar deposit in the tubes of the boilers of the Collins steamers, and explained his theory of its formation.

Dr. C. T. Jackson exhibited specimens of aluminium received from De Ville. The price of the metal in Paris is $100 a pound. Even if it should not be of great value in the arts, it would be very serviceable, from its extreme lightness, for delicate balances and weights.