"It appears to me, that there are two modes in which scientific research and investigation may tend to prevent or lessen the danger in using this article. One is, by a thorough knowledge of the chemical qualities of these ingredients, so to mix and combine them, as to render them less explosive; and the other to ascertain and point out the mode of action and operation of these fluids, and show the causes and modes of sudden and unexpected ignition, so that those who use them may easily learn, and with ordinary prudence practise, the necessary means of avoiding danger. In the hope that something of this sort can be done, I commend the subject to the continued attention of our scientific friends."

Dr. C. T. Jackson, in illustration of the views of Judge Shaw, observed, "that the use of alcohol was of the greatest importance to the agriculture of the Western States, for it was the most valuable product of Indian corn in many of those States. If corn could not be converted into alcohol and oil, it would in many places cease to be a profitable crop. Indian corn, when fermented, yielded first fifteen gallons of oil of corn (a fixed oil) per hundred bushels of corn.

"The next product was a fermented one, which on distillation yielded corn-whiskey, and the corn-whiskey passed into our Eastern States for manufacturing purposes.

"This was, in part, rectified into alcohol of ninety per cent., and that was used for the manufacture of burning-fluid, of cologne, spirits or tinctures of various kinds, &c. The ordinary whiskey was used for making white vinegar by fermentation in tuns filled with beach shavings, and this vinegar was employed in the manufacture of white-lead and sugar of lead. This vinegar was also extensively sold for making pickles and for domestic uses, and, when colored by burnt sugar, passed ordinarily for cider-vinegar, though it was not so pleasant to the taste as the true cider-vinegar.

"The oil from Indian corn has thus far been profitably separated only by the process of fermentation. It is of sufficient value to repay the cost of raising corn in the Western States, the oil being worth on the spot where made about

one dollar per gallon, which is fifteen cents' worth of oil per bushel of corn. The alcohol or whiskey was also a valuable product.

"Dr. Jackson had separated from six to eleven per cent. of pure corn oil from the eastern varieties of Zea mays, and had found most oil in the Canada and rice corn. It is contained in the gluten-cells of the grain, and is set free by decomposition of those cells by fermentation."

Three hundred and sixty-first meeting.

May 4, 1852.-MONTHLY MEETING.

The VICE-PRESIDENT, Mr. Everett, in the chair.

Professor Agassiz made an oral communication at considerable length, "On the Foundation of Symmetry throughout the Animal Kingdom."

Dr. Asa Gray communicated the characters of two new genera of plants of the order Violacea, discovered by the naturalists of the United States Exploring Expedition.

"One of these genera, of a single species, was discovered in the Feejee Islands. It belongs to the tribe Violea, having an irregular corolla, which is not unlike that of Ionidium; but the fruit is probably baccate, and the stamens are diadelphous, the posterior one being distinct from the four others. Something like this structure occurs in Corynostylis ; but the corolla of that genus is very different. The genus is named in memory of the botanical draughtsman of the expedition, the late Alfred T. Agate. I trust that the name Agàtea will be deemed sufficiently different from Agathèa and Agati to be retained.

“AGATEA, Nov. Gen.

"Calyx 5-phyllus, subæqualis, basi haud productus, deciduus. Petala 5, erecta, inæqualia; postica lateralibus paullo minora; anticum majus, labelliforme, spathulatum, basi dilatatum gibboso-saccatum. Stamina 5, diadelpha, nempe; filamenta brevia, plana, antica (glandula carnosa aucta) et lateralia marginibus connata, posticum angustius distinctum : antheræ introrsum adnatæ, loculis appositis apice liberis mucronatis ; connectivo in appendicem petaloideam latam producto. Ovarium globosum; placentis parietalibus 3 pluriovulatis. Stylus apice clavatus,

curvatus: stigma laterale. Fructus baccatus? Frutex sarmentosus ; foliis oblongis subintegerrimis ramisque glabris; stipulis minimis caducis; racemis paniculisve axillaribus multifloris; pedicellis 2-3-bracteolatis infra apicem articulatis; floribus parvis viridulis.

"AGATEA VIOLARIS, sp. nov.

Feejee Islands.

"The other genus is from the Sandwich Islands, where three species were collected by the naturalists of the Expedition. It belongs to the section Alsodinea, having a regular corolla. Indeed, it differs from Alsodeia, Paypayrola, Aubl., and Pentaloba, Lour. (if these are distinct genera), chiefly in the entirely separated stamens, with narrow filaments and normal anthers, destitute of any dilated or prolonged connective, and in the unilateral stigma, which, in a flower otherwise perfectly regular, vindicates its relationship with the genuine Violeæ. The following are the characters of the genus and species.

"ISODENDRION, Nov. Gen.

"Calyx 5-phyllus, æqualis, persistens. Corolla regularis; petala 5, lineari-spathulata, longe tubuloso-conniventia, apice dilatata patentia. Stamina 5, discreta filamenta angusta, inappendiculata, apice haud producta, antheram basifixam nudam gerentia. Ovarium, uniloculare; placentis 3 parietalibus 2-ovulatis. Stylus elongatus, subclavatus, apice decurvus: stigma punctiforme laterale. Ovula collateralia, horizontalia. Capsula coriacea, 3-sperma, 3-valvis. Semina Violæ. Arbusculæ vel frutices Sandwicenses; foliis alternis confertis; stipulis triangulatis appressis diu persistentibus; floribus axillaribus solitariis breviter pedicellatis parvis.

"ISODENDRION PYRIFOLIUM : foliis membranaceis ovalibus seu ovatoellipticis crenato-serratis petiolatis, junioribus subtus ramulisque pubescentibus; stipulis sepalisque dorso sericeis margine scariosis; floribus pendulis. Kaala Mountains, Oahu, Sandwich Islands.

"ISODENDRION LONGIFOLIUM: glabrum; foliis subcoriaceis obovatolanceolatis seu cuneato-oblongis in petiolum angustatis subrepandis; sepalis ovatis stipulisque lævibus; floribus in ramos crassos brevissime pedicellatis. Kaala Mountains, Oahu, Sandwich Islands.

"ISODENDRION LAURIFOLIUM: glabrum; foliis coriaceis oblongolanceolatis subrepandis basi obtusis brevissime petiolatis; sepalis lanceolatis. With the preceding.

"The other Violacea of the Sandwich Islands which occur in the collection are the shrubby Viola Chamissoniana of Gingins, from which

V. trachelifolia of the same author is not to be distinguished, and a new species from the island of Kauai, V. Kauensis, which has the habit of V. sarmentosa of Oregon, and nearly the structure of the Australian V. hederacea."

1

Dr. Gray also communicated the characters of a new genus of Anonacea from the Feejee Islands, dedicated to Mr. Rich, the official botanist of the Exploring Expedition, viz. :

"RICHELLA, Nov. Gen.

"Calyx subtrilobus, persistens. Corolla e petalis 6 ovatis, internis dimidio brevioribus. Torus acetabuliformis. Stamina indefinita Guatteriæ. Ovaria plura, libera, 2-ovulata: styli intus longitudinaliter stigmatosi. Ovula suturæ ventrali juxta basim inserta, adscendentia, superposita. Fructus e carpellis paucis, obovoideis, subcarnosis (siccate coriaceis), indehiscentibus, breviter stipitatis, monospermis. Semen magnum, samaroideo-nuciforme; nempe, testa coriacea marginibus alato-productis. Albumen, embryo, etc. ordinis. Arbor Uvariæ facie. "RICHELLA MONOSPERMA. Ovolau, Feejee Islands. According to Blume's arrangement of the order, this genus would stand next to Polyalthia, from which it is distinguished, as from all the others, by its winged seed."

At the suggestion of Professor Lovering, the Academy referred to the Committee on Publications an account by Mr. John Farrar, formerly Professor at Cambridge, of his observa• tions of the solar eclipse of September 17, 1811. As these observations do not appear to have been published, the committee have made the following extracts for the Proceedings:

“The place of observation is about five hundred feet southwest of Harvard Hall in Cambridge. Several gentlemen assisted me in observing the eclipse, and the following are the times, in mean solar time, with the instrument used in the observation in each case:

"In making use of single altitudes for the above times, it became necessary to determine the error of collimation of the astronomical quadrant, the diameter of the wires and the distance between them, which occasioned a delay that prevented the observations being seasonably forwarded to Mr. Bowditch, to be inserted in his valuable memoir on this eclipse."

Dr. O. W. Holmes presented the following communication "On the Use of Direct Light in Microscopic Researches,” and exhibited at the same time a model of a new horizontal microscope.

"Three points require attention in constructing a compound microscope. First, the lenses; secondly, the illuminating apparatus; thirdly, the mechanical arrangements for insuring stability in the requisite positions, and accuracy, ease, and convenience in the necessary movements.

"The lenses have been brought to great perfection by the opticians of Europe, especially of England. In our own country, Mr. Spencer of Canastota has entered into successful competition with the most eminent among them. The extraordinary merits of his lenses have been manifested in various comparative trials, the results of some of which have been made public. In a short visit I recently made to Canastota, I carried with me the one-eighth and one-twelfth objectives belonging to the instrument made by Ross for the Lowell Institute, the use of which objectives had been kindly allowed me by the Curator. In a careful comparison of them with a one-fourth and one-eighth made by Mr. Spencer, especially on the delicate tests Navicula Spencerii and Grammatophora, the superiority of Mr. Spencer's glasses was unquestionable.

"Next in importance to the perfection of the lenses, and even more important, in Sir David Brewster's opinion, is that of the illuminating apparatus. The greater number of recently attempted improvements relate to this part of the instrument. Many of the new contrivances are expensive, complicated, and somewhat difficult of management. If the same or better results can be obtained by easier means, it would be a movement in the right direction, which is always from complexity towards simplicity.

"The common mode of examining opaque objects is to receive the light directly upon them as it comes from its source, or concentrate it upon them by a lens. The use of a reflector for examining is less frequently resorted to.