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ble of sustaining a successful competition with linseed cake itself, and not more than two-thirds the market value of the latter, it now only remained to prove that its practical answered to its theoretic value. Of this there did not appear to me to be any serious doubt; nevertheless I thought it better to put the matter to the test of practical experiment. A friend to whom I named the subject readily entered into the plan of trying the effect of this cake upon a portion of his stock; the result proved his cattle would eat it with eagerness, and, as far as the experiment has gone, it has answered our highest expectations.

On a Simple Method of taking Stereomicro-photographs. By CHARLES HEISCH, F.C.S., Lecturer on Chemistry at the Middlesex Hospital. After trying various plans, the author devised the following, which answered perfectly. A microscope with its eyepiece removed is placed in a horizontal position, and fitted to an ordinary sliding back, single lens, stereoscopic camera. Behind the object-glass is screwed an adapter, in the inside of which is a tube, which can be turned half round by means of a lever from the outside. Sliding in this tube is a second, furnished with a stop which cuts off half the pencil of light coming from the object-glass, in fact occupies the same place as the prism of a binocular microscope. The distance of this stop from each object-glass is adjusted experimentally by sliding the tube backwards and forwards till the best effect is obtained. The prepared plate being put in its place after carefully focusing the object, the first picture is taken. The plate is then shifted, the stop turned half round, and the second picture taken on the other half of the plate. If the object be of any thickness, its upper surface should be focused for one picture, and its under surface for the other.

The adapter with its stop was exhibited to the meeting.

Lowe's Ozone Box. By E. J. LOWE, F.R.A.S. &c.

This box has been constructed so as to ensure perfect darkness to the test-paper without interfering with the passage of a current of air. There are two openings into this cylindrical box, the one above and the other below. These openings are not direct into the box itself, but into narrow winding passages in the first instance; they are also opposite each other. If the wind is blowing in an easterly current, and the upper opening is on the east side, then the air will enter the box on the Fig. 1. Fig. 2.

upper half (fig. 1), will move round the circular passage until it enters the central cavity (A) where the test-paper is hung, afterwards passing round the lower passage (fig. 2) in a contrary direction, and out again at the west aperture. Or if the wind happens to be in the opposite direction, it will enter from below and leave the box from above. The advantage is obvious-a current of air passes through a dark chamber. The box is small, and its price almost nominal.

Observations on Ozone. By E. J. Lowe, F.R.A.S. &c.

The following are results of observations made at the Beeston Observatory during the past four years:—

1st. If the temperature is raised, the amount of ozone will increase.

2nd. If the current of air through the box increases in rapidity, the amount of ozone will increase.

3rd. As the barometer becomes lower, the amount of ozone becomes greater. 1st. If the temperature be ranged in 10° series, a temperature between 30° and 40° will give less ozone than one between 40° and 50°, and this less than one between 50° and 60°. Artificially, if a night-light be made to burn in a cell below the box so as to warm it, there will be an increase in the amount of ozone over another box that is without a night-light. 2nd. With respect to an increase in ozone resulting from an increase in the speed of the air, it is shown from this series of observations that the most ozone has been present when there has been a gale blowing. It does not necessarily prove that under these circumstances there is actually more ozone in the air; for it must be borne in mind that if the amount of ozone in a cubic foot of air were always the same, still if today 300 cubic feet of air only occupies the same space of time in passing through the box as 100 cubic feet occupied yesterday, we shall have more ozone apparently shown today than yesterday. Then again, as chemical action increases with an increase of heat, it is also manifest that the same amount of ozone passing through the box at a temperature of 60° would necessarily darken the paper more than the same amount at a temperature of 40°.

It is quite clear that certain corrections are requisite in order to find the actual amount of ozone.

3rd. With regard to the pressure of the air, there is a striking difference between the readings of the ozonometer with a high or low barometer. Taking the four days in each month during the past year on which the mean pressure was greatest, the average amount of ozone was 1.2, whilst on taking the same number of days when the barometer was lowest, the mean was 4.1, or nearly four times as much; four years' observations give very similar results. The mean maximum pressure for the whole twelve months of the four years is 30-22 inches, the mean ozone being 10; the mean minimum pressure for the like period is 29·18 inches, the mean ozone being 3.2. With the barometer at 28 inches the mean ozone is 5.7

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There is a difference between the amount of ozone during the night and day at

different seasons.

In December and January an excess at night over the day of 0.8

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The average of the summer months being in excess only one-half of that which occurs in the winter.

On the Luminosity of Phosphorus. By Dr. MOFFAT.

If a piece of phosphorus be put under a bell-glass and observed from time to time, it will be found at times luminous, and at others non-luminous. When it is luminous, a stream of vapour rises from it, which sometimes terminates in an inverted cone of rings similar to those given off by phosphuretted hydrogen; and at others it forms a beautiful curve, with a descending limb equal in length to the ascending one. Results deduced from daily observations of the phosphorus in connexion with the readings of the barometer, the temperature and degree of humidity of the air, with directions of the wind, for a period of eighteen months, show that periods of luminosity or phosphorus and non-luminosity occur under opposite con

ditions of the atmosphere. By the catalytic action of phosphorus on atmospheric air, a gaseous body (superoxide of hydrogen) is formed, which is analogous to, if not the same as, atmospheric ozone, and it can be detected by the same tests. The author has found, by his usual tests, that phosphoric ozone is developed only when the phosphorus is luminous.

On Ferrous Acid. By W. ODLING, M.B., F.R.S.

The author found that when ferric oxide was ignited with the carbonates of potassium, sodium, and calcium, each atom of fe, O, drove out one of CO2, to form two atoms of an alkaline ferrite, having the general formula M fe 2, which salts were decomposed by water into caustic alkali and ferric monohydrate or brown hæmatite; thus, M fe 0,+H, O=H fe,+MHO.

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On the Synthesis of some Hydrocarbons. By W. ODLING, M.B., F.R.S. The author found, in particular, that when a mixture of carbonic oxide and marshgas was passed through a red-hot tube, acetylene was abundantly formed according to the equation CO+CH, CH2+H ̧O.

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On the Nomenclature of Organic Compounds. By W. ODLING, M.B., F.R.S. Admitting the impossibility of establishing a thoroughly systematic nomenclature in organic chemistry, the author advocated a gradual improvement of that now in more or less general use, by removing its chief incongruities, and remedying its more striking inconveniences. He showed, by many examples, how great an improvement might be effected by an introduction of very few and trivial changes.

On the Essential Oils and Resins from the Indigenous Vegetation of Victoria.

By J. W. OSBORNE.

The indigenous trees and shrubs of the colony of Victoria belong for the most part to the genera Eucalyptus and Melaleuca, which grow in great luxuriance over the greater part of the Australian continent. In no other localities are oil-bearing plants to be found in the same abundance, especially such as attain to arborescent growth, nor is the yield of oil as great elsewhere. The thirty-five samples submitted to the Section are identical with these exhibited in the Victorian Department of the International Exhibition. They were distilled by the Exhibitors, at the request and under the auspices of Dr. Ferdinand Müller, the Government Botanist of Victoria, to whose great talents and untiring energy the colony is largely indebted. In the present case the rigorous accuracy of the specific name of each specimen may be accepted of his authority.

The author, as Juror, examined the essential oils and resins with respect to their technological value, for the Victorian Commissioners.

Those from the genera Eucalyptus and Melaleuca (nineteen different oils) resemble the Cajuput of India, Melaleuca leucadendron. In smell and taste they are generally more camphoraceous, partaking sometimes of the odour of oil of lemon. Their colour is for the most part a pale yellow, sometimes colourless, and occasionally green. Their specific gravity, in the samples submitted to the Section, varies from 0.881 to 0.940, the average being about 0.910. These oils have all two boiling-points, the lower being, generally speaking, about 325°, and the other about 40° higher.

They burn well in suitable lamps, and are not dangerous, as they are ignited with difficulty. As solvents for resinous bodies, they surpass most liquids of the kind, and form varnishes, attacking with readiness the intractable Kauric gum of New Zealand. The yield from individuals of the series is sometimes exceedingly large, E. amygdalina giving by distillation of 100 lbs. of its green leaves and branchlets, three pints of oil; E. oleosa, 20 ounces; E. sideroxylon, 16 ounces; M. linarifolia, 28 ounces, &c. It is estimated that 12,000,000 acres of the colony of Victoria are covered with myrtaceous vegetation of this description, some of it of a shrubby character, densely covering vast tracts (E. oleosa, F. M.; E. dumosa, Cunn.; E

socialis, F. M., all known as Mallee Scrub). The other oils were chiefly endowed with medicinal characteristics, including several true mints, Mentha Australis, M. gracilis, and M. grandiflora; also some related to plants of the Rue species, and one fragrant perfume distilled from the blossoms of the Pittosporum undulatum. Also a heavy oil from the bark of the Atherosperma moschatum, possessed of powerful medicinal properties.

The resins and gum-resins include several obtained from the genus Eucalyptus, which are powerfully astringent, and more or less soluble in water. Also one from the Callitris verrucosa and cupressiformis of Northern Victoria, the sandarac of commerce; one from the Xanthorrhea australis, a balsamic resin containing benzoic acid, and resembling dragon's-blood; together with some true gums from the genus Acacia, which is well represented in the Australian colonies.

The following is a list of the oils submitted to investigation, with their vernacular names as far as known.

Eucalyptus amygdalina (Daudenong Pep- Melaleuca ericifolia (Common Tea-tree)* permint).

E. oleosa (Mallee Scrub).
E. sideroxylon (Iron-bark).
E. zonicalyx (White Gum).
E. globulus (Blue Gum).
E. corymbosa (Blood-wood).
E. fabrorum (Stringy-bark).
E. fissilis (Messmate).
E. odorata (Peppermint).
E. Woollsi (Woolly-butt).
E. rostrata (Red Gum).
E. viminalis (Manna Gum).
Melaleuca linariifolia.

M. curvifolia.

M. Wilsonii.

M. uncinata.

M. genistifolia.
M. squarrosa.

Atherosperma moschatum (Sassafras).
Prostanthera lasianthos.

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Details of a Photolithographic Process, as adopted by the Government of Victoria, for the publication of Maps. By J. W. OSBORNE.

The author referred to his having read a paper upon this subject before the Royal Society of Victoria, in November 1859, his process having been previously patented in the Colony on the 1st of September, 1859. The process had then been adopted by the Government, and had come info active use in the Department of Lands and Survey at Melbourne. By its means many hundreds of maps had been published, of a quality and for a price which left nothing to be desired. The Victorian Government had recently erected an office, the design and arrangements of which were admirably adapted for the prosecution of this description of work. To produce a photolithographic copy with or without reduction, the original map or engraving was extended upon an upright board, and by the help of a camera placed opposite, a negative of it was taken. A sheet of paper was now prepared by coating one of its surfaces with a solution of gelatine in water, to which a certain proportion of bichromate of potash and liquid albumen had been added. The surface thus prepared, after it had dried in a dark and warm room, was sensitive to the chemical action of light, and the next operation was to expose to the sun's rays a suitable piece of it, in an ordinary pressure frame, under the negative already obtained. The positive photographic print thus produced was inked all over with lithographic re-transfer ink, and was then placed floating upon boiling water, with its inky side upwards and unwetted. After a short time the gelatine would be found to have softened and swelled under the ink, save where the light had acted, the organic matter upon such places having suffered a peculiar change. Another effect of the boiling water was to coagulate the albumen in the film. When sufficiently soaked, the superfluous ink was removed by means of a sponge, and the result was a photographic print in greasy ink; inasmuch as the latter substance adhered firmly to all the unsoftened, or, in other words, the altered parts of the gelatinous coating. It would also be found that the delineation thus obtained was upon a smooth sur 1862.

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face of coagulated albumen. Boiling water in abundance was now poured over the paper, after which it was carefully dried. The photographic print thus produced, in consequence of the greasy ink upon the positive portions of the work, was capable of being transferred to stone by the printer, by the well-known mechanical process; and from stones thus prepared, impressions could be pulled in the lithographic press. Numerous specimens were exhibited to the Section.

On the Manufacture of Hydrocarbon Oils, Paraffin, &c., from Peat.
By B. H. PAUL, Ph.D.

The author described the results that had been obtained at some works lately erected under his direction in the island of Lewis, N.B. The peat of that locality was described as a peculiarly rich bituminous variety of mountain peat, yielding from five to ten gallons of refined oils and paraffin from the ton. The results obtained at these works were contrasted with those obtained at the works of the Irish Peat Company some years ago, where the produce of oil was not more than two gallons from the ton of peat. This difference in the produce was ascribed, in a great degree, to the improper mode of working adopted at the Irish works. One of the most important points dwelt upon was the necessity of regarding the hydrocarbon oils and paraffin as the only products that would afford a profit in working peat; and the failure of the Irish works was attributed to the attempt to obtain other products which could only be regarded as waste, and not worth working, unless the oils and paraffin were obtainable in a remunerative amount from the peat.

On the Decay and Preservation of Stone employed in Building,
By B. H. PAUL, Ph.D.

The causes and nature of the decay of building-stone were described as being both chemical and mechanical, and varying according to the nature of the stone and the conditions to which it was exposed. The various methods which have been proposed for the preservation of stone from decay were described in detail; the author considering, from a chemical point of view, that none of them presented any probability of success in effecting the desired result, and that the discovery of an efficient and practicable means of preventing the decay of stone, especially in towns, still remains to be made.

On the Artificial Formation of Populine, and on a new Class of Organic Compounds. By T. L. PHIPSON, M.B., Ph.D., F.C.S. &c.

The interesting substance populine was extracted in 1830 by Braconnot from the mother-liquors which had deposited salicine when the latter was obtained from the leaves and the bark of the pop'ar tree (Populus tremula). It was submitted to an important series of experiments by Piria in 1852, who found, among other interesting facts, that, in a variety of circumstances, populine split up into benzoic acid and salicine:

C40 H22 016+ 2 HO= C14 H3 O3, HO+ C26 H18 O1a,

Populine.

Benzoic acid.

Salicine.

It occurred to me that salicine and benzoic acid might be combined so as to reproduce populine. And this I find to be the case: when equal equivalents of salicine and benzoic acid are dissolved in alcohol and the liquid evaporated to about half its bulk, magnificent acicular crystals of populine are obtained, some of which in my experiments measured nearly an inch in length. For every 100 parts of salicine must be taken 43 parts of benzoic acid. Or for 100 parts of salicine, 53.5 parts of benzoate of soda and a sufficient quantity of diluted sulphuric acid to saturate the soda of the benzoate; alcohol is then added, and the sulphate of soda separated by filtration. By evaporating the solution long needles of populine are obtained:

C14 H6 O+C26 H18 014= (C40 H22 016 +2 HO).
Benzoic acid. Salicine. Crystallized populine.

The properties of the populine thus formed are precisely those of the natural

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