3. Oil of Bordeaux turpentine rectified without water.-M. Guibourt took 2 kilogrammes 250 grammes [about 6lbs. troy] of good oil of Bordeaux turpentine, and put it into the cucurbit of an alembic, and distilled, without the addition of water, 500 grammes [about 1lb. troy] of oil. The oil had a density of 0.871 at 48° Fahr.; and with a column of 100 millimetres, it produced a left-handed deviation of 37° 8.

4. Oil of Bordeaux turpentine, rectified with water. First product. After the preceding oil had distilled over, M. Guibourt put some water, and again submitted the oil to distillation. The oil obtained had a density of 0.872, and its left-handed deviation, for a column of 100 millimetres was 36o.

5. Oil of Bordeaux turpentine, rectified with water. Second and ulterior products.-The last portions of oil obtained by distilling the oil with water, were feebly yellow, less fluid than the first products, and, when poured out, a little filamentory. Its density was 0.889 at 48° Fahr.; and its left-handed deviation 26° for a column of 100 millimetres.

"It results from these experiments," says M. Guibourt, "that the oil of Bordeaux turpentine contains at least two oils of different densities and volatilities, and which do not act equally on polarized light; the last product of rectification acting much less feebly than the first. The unrectified oil, consequently, ought to produce a left-handed deviation intermediate between the first and the last rectified product."

6. Strasburgh turpentine; turpentine of the silver fir (Abies picea, or Abies taxifolia). It had a citron odour, was quite transparent, almost liquid, and had a pale yellow colour. It was examined in a square flask. It had a left-handed rotation of 5° for a thickness of 70 millimetres [=2.75 English inches.]

7. Oil of Strasburgh turpentine, obtained by distillation. from the preceding turpentine. Its specific gravity at 53.6 Fahr. was 0.861. Its left-handed rotation at the temperature of 59° Fahr., for 100 millimetres, was 13°2 for the flax-flower tint.

8. Larch turpentine; genuine Venice turpentine; turpentine of Larix Europea. Left-handed rotation 5o9.

9. Oil of balsam of Canada, obtained by distilling balsam of Canada without water. Rotation left-handed, for a column of six inches, 35° for the flax-flower tint.

10. Resin of Balsam of Canada.-Rotation left-handed.

2. RIGHT-HANDED OR DEXTRO-GYRATE TURPENTINES. 1. Rectified oil of turpentine of English commerce, obtained from American turpentine, the produce of Pinus palustris chiefly, and Pinus tæda.

Its density at 53.6 Fahr. was 0.867. Its right-handed rotation for a column of 108 millimetres [4.25 English inches], at a

temperature of 59° Fahr., was 22° 5, for the violet blue tint, and for the rays transmitted by red glass, from 16° 9 to 17°.

2. Balsam of Canada, obtained from Abies balsamea. In a cylindrical vessel of about 50 millimetres [1.96 English inches] in thickness, its right-handed deviation was 6°.

I have subsequently examined balsam of Canada, from several sources, and find them all right-handed.

"This opposition (in the optical properties of the two balsams obtained respectively from Abies picea and Abies balsamea) is," says M. Guibourt, "very remarkable, on account of the great affinity which exists between the trees, as well as of the remarkable similarity which exists between the chemical properties of the two balsams."

ON SOME VEGETABLE AND MINERAL PRODUCTIONS OF NEW ZEALAND.

DR. PEREIRA laid before the Committee specimens of some vegetable and mineral substances recently brought from New Zealand, and which he had received from Mr. W. Brown, formerly of that country, and who was desirous of ascertaining their properties and commercial value. Dr. Pereira arranged them in natural historical order, and appended a few observations to each.

1. MINERALS.

The mineral substances consisted of native sulphur, from White island; a substance commonly called magnesia, and said to be dug out of the ground in the neighbourhood of Auckland; black oxide of manganese from the isle of Waiheke, copper ore from the island of Kawau, and brown coul.

The substance erroneously denominated magnesia, is a soft, white, light mass of siliceous animalcules. It has been examined microscopically both by Mr. Bowerbank and Mr. H. Deane, the former of whom states that it consists of several species of gallionella, a few species of navicula, and others, intermixed with a small quantity of sand. I understand that a similar error was made in America; an animalcular mass of silica being mistaken and used for magnesia!

2. VEGETABLES.

The vegetable substances have been arranged according to the natural orders of the plants yielding them.

1. Smilacea, R. Brown.-Specimens of the cut stems, the leaf, berry, and extract of the stems of a plant called by the

natives kareao, the Ripogonum parviflorum of Robert Brown. (See Allan Cunningham, in Hooker's Companion to the Botanical Magazine, vol. ii). It is said to possess similar virtues to those of sarsaparilla, a statement by no means improbable, considering that it belongs to the same natural family as the genus Smilax. Should experience confirm the truth of the statement, the plant might be conveniently called New Zealand sarsaparilla. The stems are said to yield 12 per cent. of extract. The specimen of extract furnished me is slightly bitter, and contains starch-gum and traces of astringent matter.

2. Conifera, Lindley.-The cowdie-pine resin, also known as kouri resin, or cowdie gum, is obtained from a coniferous plant, growing exclusively in the northern portion of the Northern Island. It is the kouri or kauri of the natives, the Dammara australis of Don, and Agathis australis of Salisbury. A botanical description of this tree is given in Mr. Lambert's second edition of his splendid work on the genus Pinus, and also in Loudon's Arboretum et Fruticetum Britannicum, vol. iv.

The resin exudes from the stem spontaneously, and by incision (Bennett, London Medical Gazette, vol. ix, p. 149). It is also found underground in various parts of the same island, where the pine trees now no longer exist. My informant, Mr. W. Brown, tells me that he has found it at the depth of at least two feet. Dieffenbach (Travels in New Zealand, vol. i. p. 201, 1843) also alludes to the existence of this resin scattered over the surface of the ground in certain parts of the Northern Island, where, in not very remote times, the cowdie pine must have grown, though it is now no longer found there. The resin which has exuded from the stems of trees now in existence, has a more or less milky or opalescent appearance, and in the more recent specimens is somewhat odorous; whilst those samples which have been buried in the earth are transparent, more nearly resemble amber in colour and appearance, and are quite devoid of odour. The American dealers prefer the latter sort. years ago, this resin was described by Mr. Prideaux (Lond. and Edinb. Phil. Mag., vol. xii., p. 249, 1838). His examination of it had a special relation to its employment in the arts; and he suggested its applicability to the manufacture of varnishes, sealing wax, and resin gas for the purposes of illumination.

Some

It is extensively employed, I am informed, by the Americans, who purchase it at New Zealand. Mr. Darwin (Narrative of the surveying Voyages of Her Majesty's Ships Adventure and Beagle, vol. iii., p. 510, 1839), says, that it is sold to them at a penny the pound, but that its use is kept secret. Mr. Wm. Brown, however, informs me that they readily purchase it at New Zealand at £16 per ton; and on one occasion, a captain

gave £45 per ton for it. He understood that it was employed in America, as a substitute for copal, in the manufacture of varnishes; not to the entire exclusion of the latter resin, but mixed with it, in the proportion of one part copal to three parts cowdie resin.

Recently Dr. R. D. Thomson (Lond. Edinb. and Dubl. Phil. Mag., vol. xxiii., p. 81, 1843) has submitted cowdie resin to chemical examination, and found that it consists of two resinous substances, the one acid, and called by him dammaric acid; the other neutral, and termed dammaran. The first is soluble in weak alcohol; while the second is insoluble in weak alcohol, but is soluble in absolute alcohol. The formula for the entire resin, as well as for dammaran, is C40 H31 O6; while that for anhydrous dammaric acid is C40 H30 06.

3. Taxaceae, Lindley.-The collection given me by Mr. W. Brown contains two substances belonging to the family taxacea.

One of these is called by the natives Tanekaha. It is the Phyllocladus trichomanoides of Don. Specimens of the bark leaf, and extract of the bark, have been sent. The bark is used in dyeing red. Mr. W. Brown tells me that boat sails are dyed with it to preserve them. One pound of the bark is said to yield sixty-three grains of tannin.

The extract given to me by Mr. Brown has a beautiful ruby red tint; its taste was astringent. Its solution in water produces with gelatine a precipitate, and with the persalts of iron a dark green colour.

The other taxaceous plant is that called by the New Zealanders Rimu. It is the Dacrydium cupressinum of Solander. Specimens of the bark, branch with leaves, exudation (which is said to resemble kino), and extract of the bark have been sent. One pound of the bark is said to yield eighty-five grains of

extract.

4. Saxifragaceae, De Candolle.-To this order belongs the plant, called by the natives of New Zealand Towai; by Don, Leiospermum racemosum; by De Candolle, Weinmannia racemosa. (See Allan Cunningham, in the Annals of Natural History, vol. ii., p. 358). Specimens of the bark, extract of the bark, and leaf have been sent. The bark is in long pieces, which by a superficial observer might be confounded with red cinchona bark. It is supposed to be valuable for the purposes of the tanner, and is said to yield 104 grains of tannin for every pound of bark.

5. Meliacea. Specimens of the wood with the bark, of the leaf, and extract of a plant, called by the natives koa-koa. It is the Hartighsia spectabilis of De Candolle. It is said to possess the properties of gentian, and to have been substituted

for hops in the manufacture of beer. The leaves yield a very bitter extract.

6. Myrtacea, De Candolle.-The plant called by the natives Pohutu-kawa is the Metrosideros tomentosa of Richard, the Callistemon ellipticum of Allan Cunningham. (Annals of Natural History, vol. iii., p. 113). Specimens of the wood, with the bark, and of the leaf, have been sent. It is thought that the bark may be useful for tanning: one pound of it is said to yield sixty grains of tannin. Mr. W. Brown tells me that this bark is supposed to contain an alkali.

7. Elæocarpeæ, Jussieu.-The tree called by the New Zealanders the Hinau, is the Elaeocarpus hinau of Allan Cunningham, (Annals of Natural History, vol. iv., p. 23); the Dicera dentata of Forster. A large log, forming a portion of the stem, and a specimen of the bark, of the leaf, and of the extract, have been sent. The bark is used by the natives for dyeing black. A watery solution of the extract produces a precipitate with gelatine, and a blueish black colour with the salts of iron. The New Zealand flax (Phormium tenax) is first steeped in a decoction of the bark, by which it acquires a brownish tint, and is then placed in mud which strikes a fine black colour. Specimens of the raw flax, of the flax which had undergone the first stage of dyeing black, of the ferruginous mud or earth, and of flax dyed black, have been sent. Mr. W. Brown states, that the flax cultivated by the natives for the manufacture of their finer kind of mats, is very superior to the coarse kind of flax which grows wild, and which they have usually supplied to Europeans.

Uncertain. A sweetish astringent bark, called by the natives Towai (not the Weinmannia racemosa beforementioned), has been sent, but nothing could be made out respecting its natural history.

ORIGINAL AND EXTRACTED ARTICLES.

TEST FOR ADULTERATIONS IN DISULPHATE OF

QUININE.

BY J. BIRKBECK NEVINS, M.B.

A SAMPLE of suspected disulphate of quinine having been sent to me for examination, I was induced to seek a more simple test for the presence of sugar than the one usually proposed. When the salt is dissolved in dilute sulphuric acid, and the alkali precipitated by means of liquor potassæ or ammonia, the direction generally given is, to evaporate the solution, and taste whether or not it is sweet. If however, the quantity of