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species of Botrychium may be found, with a view to determine the question.

The American Compass Plant.-Dr. Thomas Hill, who read a paper on this subject before the American Association at the last meeting, says that in June, 1869, as he was coming from Omaha to Chicago, on a very dark rainy day-80 dark that he could not form any estimate of the points of the compass from the sunlight-at three different points on the prairies he Doticed young plants of Silphium laciniatum, and estimated from them, while going at full speed, the course of the railway track. On reaching Chicago be procured, by the kindness of the officers of the C. & N. W. road, detailed maps of the track, and found where he had estimated the bearing at 35°, 75°, and 90°, the true bearings were 31°, 789, and 90°. In October, 1869, being detained by an accident at Tama, he gathered seed, and this spring raised a few seedlings. Drought and insects destroyed part of them, and he could only give the history of eight plants, with fourteen leaves. Ten of these fourteen leaves showed a strong disposition, when about four inches high, to turn to the meridian ; the other four showed a feeble disposition in the same direction. These ten leaves, on coming up in June, had an average bearing of 42°, and the mean bearing was nearly as large. But in August the same ten leaves showed an average bearing of only 41°, and the mean bearing was but 21. Dr. Hill refers this polarity to the sunlight, the two sides of the leaf being equally sensitive, and struggling for equal shares. Ile hoped in a more favourable summer to test this, and several other points which had suggested themselves, by experiments.

Scleroderma vulgare an Eatable Fungus.— The Food Journal (an interesting periodical, which we are glad to see succeeding) contains a very interesting note on the above by the Rev. M.J. Berkeley,F.R.S., in the December number. It is as follows:-_“I was somewhat surprised some time since, amongst a host of other enquiries respecting the qualities of particular fungi, to have Scleroderma vulgare submitted to me; and still more so, after my evil report of it, to find that it had been largely eaten and pronounced very good. It is only in the young state, of course, that any question could arise about it, for like its allied puff-balls, when old, it is filled with a mass of loathsome dust. I ought, however, to have recollected that its use as an article of food was no novelty, as under another and false name it has been largely employed at Paris instead of the truffle of Périgord, to adulterate Périgord pies, the quality of which was, in consequence, much deteriorated. Young specimens were given by the late Monsieur Desmazières in his Plantes Cryptogames du Nord de la France,' Fasc. xvi., 1836, as specimens of the white trutile, though the structure is totally different. It is found abundantly in the neighbourhood of Mons, where it frequently appears in the market, and is sent from Belgium, in great quantities, to Paris. Some pains are taken to guard it in the place of its growth, by covering it with earth, until of sufficient size, against the ravages of animals, but especially of the magpies. The same thing clearly is figured by Corda, under the name of Pompholy.x lupidum, who considers it superior to either the black or white truflle. I am not certain whether Dr. Bull, who is such an authority on the subject, has really tried its culinary properties; but in a letter, recently received, he Bays, 'I am afraid Scleroderma vulgare, though doubtless edible when

young, like all the other puff-balls, will scarcely do to recommend as edible, since it is so small and not attractive by its colour, even when young, and very dangerous at an earlier stage. There seems always to be conflicting evidence about the quality of fungi, the truth probably being that the same species may be wholesome or the contrary, according to local or climatic condition, or from idiosyncratic peculiarities of constitution. Sparagris crispa, one of the largest and most beautiful of our fungi, has occurred lately in two or three localities; and I have myself had some dressed which came from Miss Broadwood, of Lyne, in Hampshire, which proved excellent. A single specimen, like Lycoperdon giganteum, is so large that it would almost be sufficient for a Lord Mayor's feast.”

Nutrition and Sex in Plants.-In the American Naturalist for November, Mr. Thomas Meehan gives a short account of his paper on the above subject. He refers to his “laws of sex," read last year, and now proposes to show that a decreased power of nutrition is one of the operating causes against that high state of vitality necessary to produce the female sex. He stated that there were two classes of male flowers on the common chestnut (Castanea Americana), one from the axils of leaves on weak branches, the other terminating the vigorous shoots, only on which the female flowers are formed. The axillary male flowers mostly matured before the supra-pistillate ones opened. These were extremely weak, owing to the superior-absorptire power of the females below them. He then exhibited some specimens of these, as well as some from a very large chestuut tree, which had always borne abundant fruit, but had this year produced nothing but male flowers. The leaves were all striped with yellow and green, indicating, as every experienced gardener knows, that nutrition was obstructed. Plants orer watered, by which the young feeding roots rotted, always put on this yellow cast. The yellow tint always followed “ringing " the branches, or any accident done to the bark. The influence of this defective power of nutrition, in this instance, he held so clear that he had no difficulty in concluding that it was one of the agents which operated on the laws of vitality that governed the sexes.

Difference of Sex with Difference of Station. It is a very curious fact that there are many plants common to this country and America which present different sexual characteristics in the two. At a late meeting of the Philadelphia Academy of Science, Mr. Meehan exhibited some specimens of Rumex oblongifolius, a naturalized dock from Europe. He said that so far as he could ascertain from European specimens, and the descriptions of Babington, Bromfield, and other English botanists, the plant was there hermaphrodite ; but there, as correctly stated by Dr. Asa Gray, it was monaciously polygamous. He thought the fact that plants hermaphrodite in one country becoming unisexual in another was worthy of more attention by those engaged in the study of the laws of sex than had been given to it. This Rumex did not stand alone; R. crispus and R. patienta exhibited the same thing. Fragaria was another instance well known to horticulturists, although the fact scientifically had not received due weight. The average tendency of the strawberry in Europe was to hermaphrodism_here to produce pistillate forms. He also called attention to the fact that in these American specimens unisexuality was in proportion to axial rigor. This law

he had already explained in times past to the Academy, and new instances were scarcely necessary. Here, however, the moderately weak plant had more hermaphrodite flowers than the strong one; and in both classes of specimens the number of male flowers gradually increased with the weakening of the axis, until the ends of the raceme were almost wholly of male flowers. The first flowers on the strong verticels were usually wholly pistillate.

CHEMISTRY. The Filtration of Strong Acids.- Dr. James St. Clair gives the following simple and exact method in the “ Chemical News' of September 30: “Into the narrow part of an ordinary glass funnel, spun glass (such as is used in making tails for glass birds) is closely packed, and over this is sprinkled ground glass to the depth of a quarter of an inch, care being taken that both the funnel and glass are perfectly clean. About four ounces of boiling water are then allowed to pass through the filter, which is then allowed to dry, and, previous to being used, is moistened with a pure specimen of the acid to be filtered. A filter so constructed is as efficient as any with which he is acquainted, is very durable and cheap, while, from the fact that these acids do not act on glass, freedom from contamination during the process is perfectly ensured. Such filters, or the materials necessary for their preparation, may be obtained at Mr. Motherwell's, 73 Union Street, Glasgow.”

What is Thymol ?—The “Medical Press " of December 7 says that Mr. Henry Draper, of Dublin, exhibited to the Dublin Chemical Club, at its last meeting, a specimen of a new preparation which has been proposed as a substitute for carbolic acid. It is named thymol, and is a derivative of the Thymus vulgaris, the monarda or horse-mint, and the Ptychotisan East Indian umbelliferous plant. It is of a similar chemical composition to carbolic acid, but destitute of the very unpleasant smell of this popular disinfectant. It melts at 44° Centigrade, and is soluble in 300 parts of water. It resembles carbolic acid in forming compounds with potash and soda, but differs from it in that these compounds are very unstable, being decomposed even by carbonic acid. The introduction of this preparation recalls to mind the fact, that oil of thyme was in past years a favourite popular remedy for the toothache, and it is only now that its efficacy and the causes of such efficacy have been made manifest. The oil of thyme is prepared in large quantities in the south of France, where it is used for printing on china.

Acid Nature of the Organic Matters in River Water.-Herr F. Stolba, writing in the second number of “Dingler's Journal ” for October, states that, according to his experience, obtained by making (in Bohemia) a large number of water analyses, all waters which contain a large proportion of organic matter contain it in combination with bases, chiefly lime, and that, therefore, the organic matter is (as already sugyested, and partly experimentally proved by Berzelius) of an acid nature.

Death of Professor Miller.The “Chemical News" gives the following sketch of Professor W. Allen Miller, M.D., F.R S., Professor of Chemistry in King's College, who died on October 30, 1870. He died at Liverpool,

whither he had gone to take part in the proceedings of the British Association. Dr. Miller was born at Ipswich, on December 17, 1817, and in his twenty-fourth year he became assistant to the late Mr. Daniell, Professor of Chemistry in King's College, London. In 1844, he co-operated with his master in the publication of a paper on the “Electrolysis of Secondary Compounds.” In the following year he was elected a Fellow of the Royal Society, and succeeded Mr. Daniell in the chair of chemistry in King's College. His chief work at this time was his paper on the “Spectra of certain Vapours," published in 1845. In 1849, he again came before the scientific world with a paper on the “Atomic Volumes of Organic Liquids." From this date his time appears to have been chiefly absorbed by other than purely scientific subjects. He held the posts of treasurer of the Royal Society, president and afterwards vice-president of the Chemical Society, and assayer to the Royal Mint, besides being member of the Science Commission. His later contributions to the scientific periodicals were, a paper on “ Transparency," in the “ Journal of the Chemical Society," some “ Analyses of Gutta Percha," and “A Treatise on Potable Water.” In conjunction with Mr. Huggins he investigated the spectra of the fixed stars. He is known to the educational world by his voluminous and widely popular “Treatise on Chemistry," in three parts, which originally appeared from 1855 to 1857, and which has already gone through several editions. Although Professor Miller was not a member of the Society, he took an active interest in its operations, and served on several of its committees.

The Theories of Fermentation. In the “Bayerisches Industrie- und Gewerbe-Blatt" (August), Herr Dr. A. Weinberg gives a very exhaustive paper on the above subject. It was originally a lecture before the Chemical Society of Munich, and deals as follows with the several investigators who deserve to be named in connection with the subject: 1. Those who consider fermentation to be a purely chemical process, the result of the chemical action of the ferment or yeast on the sugar; MM. Trommsdorff and Meissner are the founders of this theory. 2. Those who consider fermentation to be a process of galvanic decomposition, called forth by the dualism of the exciting body in a conducting fluid ; this theory was founded by M. Kämtz, and among its adherents are MM. Schweigger, Colin, and Kölle. 3. Those who consider it as a catalytic process, or as due to the action of porous bodies; this theory was founded by M. Berzelius. 4. Those who consider that fermentation is due to the action of certain nitrogenous matter, which is itself permanently in a state of decomposition, which is imparted to the sugar as soon as it (the sugar) comes into contact with the decomposing nitrogenous matter under favourable conditions, the consequence being the splitting up of the sugar into alcohol and carbonic acid ; this view has been established by Dr. von Liebig, and is adhered to, among others, by MM. Frémy, Löwig, Gerhardt, &c. 5. Lastly, fermentation is viewed as being a kind of process of vegetation, the newly-formed yeast being considered as the newly-generated plant; this view is held by MM. Erzleben, Cagniard-Latour, Schwann, Dumas, Mulder, and others.

The Manufacture of Iodine, according to Professor Wagner, already amounts to 30,000 pounds a year.

Analysis of Birmingham Water.Dr. IIill read a paper before the British

Association, which is reprinted by the "Food Journal” for December. The revelations then made as to the qualities of the shallow well-waters are such as to shock the feelings of any thoughtful man. The table is too long to quote in full, but a few facts from it will suffice. The total solid impurities per gallon figure in enormous amounts, such as 256, 380, and even 507 grains per gallon; while the organic contamination runs through a rising scale till it reaches the almost incredible figure of 48:16 grains per gallon, in the very water holding 507.02 grains of solid matter in each gallon.

Composition of the Water of the Nile.—The water of the Nile has recently undergone investigation by Herr0. Popp ("Annalen der Chemie,” September). The sample of water taken for analysis was obtained from the middle of the river, some six miles below Cairo. Previous to being analysed, the water was left standing for two days, after which time the water was first filtered ; but, even after this operation, it did not become quite clear, and it was found necessary, consequently, to leave it standing for some few days longer, when it deposited a flocculent sediment, which, on being tested, was found to consist of silica, a minute quantity of organic matter, lime, and magnesia salts. One litre of the water contains, in grammes weight-carbonic acid, 0-03146; sulphuric acid, 0·00390; silica, 0·02010; phosphoric acid, 0.00054; chlorine, 0:00337; peroxide of iron, 0.00316; lime, 0.02220; magnesia, 0-01467; soda, 0·02110; potassa, 0.00468; organic matter, 0.01720; total, 0.14238 grm. Percentage composition of dry residue-carbonic acid, 22.155; sulphuric acid, 2-755; silica, 14:150; phosphoric acid, 0:379; chlorine, 2:372; peroxide of iron, 2-227; lime, 15.640; magnesia, 10:332 ; soda, 14.852; potassa, 3.300; organic matter and small quantity of ammoniacal salts, 12-025; total, 100.187.

Detection of Sulphur in Coal-Gas.-In a recent number of the “ Journal für Gasbeleuchtung,” Herr Ulex gives the following method. Let a platinum basin be filled with half a litre of water, and the basin be heated over a Bunsen-burner until all the liquid has evaporated; the basin will be found to be coated, on the outside, where it has been struck by the flame, with a dirty, greasy looking substance, which, on being washed off with pure distilled water, and tested, proves to be sulphuric acid. The author further points out that the glass chimneys used with Argand gas-burners soon become coated over internally with a white substance, which, on being washed off with distilled water, will be found to be, on testing, sulphate of ammonia. The glass panes of a room wherein gas is burned for a few evenings consecutively will, when rubbed with the fingers of a clean hand, impart to it a substance which, on the hand being rinsed in distilled water, will yield a precipitate of sulphate of baryta with chloride of barium, and a brick-red precipitate with potassio-iodide of mercury.

Powdering Camphor.-In the “American Journal of Pharmacy” for November, Mr. W. Proctor gives some hints as to the above. It is well known that camphor is easily reduced to powder by rubbing with a few drops of alcohol, but the powder so made will, after a short time, aggregate to crystals, which have to be rubbed down again. The author mixes with the powder of camphor so obtained, carbonate of magnesia, 10 grains to the ounce being sufficient; this powder never cakes or forms crystals.

A Sensitive Test for Hyposulphites is given by Dr. Boëttger in the “Journal

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