it with very little expense, which will be to those who use gall a great saving, as it will prevent it from putrefying or breeding maggots.

One gall prepared in my method will serve an artist a long time, as it will keep a great number of years. It will be a conven'ent article for use, as a small cup of it may be placed in the same box which contains other colours, where it will be always ready. The qualities of gail are well known to artists in water-colours, particularly to those who colour prints, as many colours, will not, without gall, work free on such paper, on account of the oil that is used in the printing-ink.

The artists who make drawings in water-colours also use gall in the water which they mix their colour with, as it clears away that greasiness which arises from moist hands upon paper, and makes the colour to work clear and bright. My preparation is ready for use in a few minutes; all that is necessary being to dissolve about the size of a pea of it in a tablespoonful of water.

It is also of great use to housekeepers, sailors, and others, to clean woollen clothes from grease, tar, &c. and will be found advantageous for many other purposes.

If it should meet with the approbation of the Society, I have no objection to prepare it for sale. I am, sir,

your obedient servant, RICHARD CATHERY, Botanical Colourer.

To C. Taylor, M.D. Sec.

Process for preparing Ox-gall in a concentrated state, by Mr. Cathery.

Take a gall fresh from the ox and put it in a bason, let it stand all night to settle, then pour it off from the sediment into a clean earthen mug, and set it in a saucepan of boiling water over the fire, taking care that none of the water gets into the mug. Let it boil till it is quite thick, then take it out and spread it on a plate or dish, and set it before the fire to evapo-. rate; and when as dry as you can get it, put it into small pots, and tie papers over their tops to keep the dust from it, and it will be good for years.

Certificates were received from Mr. Gabriel Bayfield, No. 9, Parkplace, Walworth, and Mr. William Edwards, No. 9, Poplar-row, both botanical colourers, stating, that they have used the ox-gall prepared by Mr. Cathery, and find it to answer better than gall in a liquid state; that this preparation is free from disagreeable smell, and is much cheaper, as one ox-gall thus prepared will last one person for two years, and be as fresh as if just taken from the ox.

A certificate was received from Mr. James Stewart, No. 26, St. Martin's-street, Leicester-square, stating that he lately belonged to his Majesty's ship the Vestal frigate, and that he took out with him in a voyage to Newfoundland a large pot of the prepared oxgall, for the purpose of washing his greasy clothes for two years; that he found it very serviceable, and to keep its virtue as well as the first day.

Method

Method of procuring Turpentine and other Products from the Scotch Fir. By Mr. H. B. Way.*

[From the Philosophical Transactions of the Society of Arts, &c. Vol. XXVIII. for 1810.]

SIR,

The enormous high price of turpentine, tar, and pitch, last year, brought to my remembrance that I had, in 1792, when in America, made some memorandums on the subject of obtaining them in North Carolina, which, on referring to, led me to think that they might be obtained in this country. I was induced to mention it to my relation and friend, John Herbert Brown, Esq. of Weymouth, and of Sheen, in Middlesex, when on a visit at my house, and I expressed a wish that I could try the experiment with regard to turpentine; when he very kindly gave me leave to try it on three trees growing on his estate, about three or four miles from this place, and he went with the and fixed on them, and early in last April I had them prepared for the purpose of extracting the turpentine, and they have been running till the 18th instant. The weather, except the last month and part of this, has, from so much rain falling, and there being so little hot weather, been particularly unfavourable for this business, as, the distance being such as to prevent the trees being regularly attended, the hollows were frequently found by my men full of water, and a good deal of

the turpentine, which ran off with the water, lay on the ground. Under all these circumstances I was only able to obtain from the three trees about two pounds and a half of turpentine.

Mr. Brown being with me again the 16th and 17th instant, as be wished to take the trees down, I begged he would allow me to to take a part from one of them, for the purpose of sending to the Society of Arts, Manufactures, and Commerce, with the turpentine collected from the trees; which he most readily complied with. I have therefore taken about six feet from one of them (they are all nearly the same size); what I have sent is the part from the ground to the top of the place that has been cut away for the turpentine to run into the hollow, from whence it was to be collected; the hollow was cut in this considerably higher than is usual in America, as this tree stood in a hedge, and could not well be hollowed lower. I have matted up this part of the tree, and secured it with straw and a double mat, to prevent the bark being rubbed off, that it may be seen in the same state as it stood when the turpentine was taken from it. The turpentine is in the cask in which it was deposited when brought from the trees; and I have this day shipped both on board the sloop Betsey, Captain Trent, bound to Downes's Wharf, London, directed to you, freight paid here by me, which vessel I expect will sail in a day or two, and I hope you will receive them safe

which

which when you do, you will much oblige me by requesting that both may be examined, in the hope that this small trial may meet with the approbation of the very highly respectable and truly useful Society of Arts. Manufactures, and Commerce; and if considered likely to prove useful, that they may induce some person who has the means and opportunity of doing it, to make a trial on a larger scale, so as to fairly ascertain whether turpentine can be obtained in this country from the very large and numerous plantations of Scotch firs, now in the United Kingdom, previous to the trees being cut down, either to thin plantations, or where ground is designed to be cleared, as taking the turpentine from the trees previous to their being cut, does not at all injure the wood, but by making the hollow in the trunk of the tree about six inches from the ground, it would waste but a very small quantity of timber.

I have taken the liberty of annexing a copy of memorandums I made when in North Carolina, respecting the modes of collecting turpentine, and making tar and pitch, in hopes they may afford the society some little information, as they are not, I apprehend, very generally known. They are copied from memorandums which I actually made on the spot. I would have sent the memorandum books with this, had not the remarks been mingled with others relative to my commercial pursuits; but I shall have no hesitation in allowing any person to examine them, or to afford any information in my power to any

persons willing to make experiments in this way, if they will favour me with a call. I am well satisfied in my own mind, that very large quantities of tar might be obtained from the knots and limbs of the Scotch fir when cut down, and that the charcoal made from it would not be injured by the tar being first extracted, and as I was in Norway, Sweden, and Russia, in 1789 and 1790, and saw no tree from which I consider that tar could be extracted, exexcept the Scotch fir, or red deal, which is one and the same tree, I am persuaded that the refuse of that tree must be what they make the tar froin in those countries, though I had no opportunity of seeing the process there. I suspect that the Swedish tar-kilus must be constructed of brick, or some sort of masonry, as the tar from thence is much clearer, better, and more free from extraneous matters than that of any other country.

I have observed the tar from North Carolina to have frequently a quantity of sand in it, which is easily accounted for, from the soil in which the kilns are made; it would, in the careless way in which they take it out of the hole dug in a sandy soil, be very likely to be mixed with the sand. In the small cask, in which the turpentine is, I have sent a few small red deal knots from some timber that I have lately taken out of my warehouse, on some alterations being made; the timber from which they are taken has been in the warehouse ever since the summer of 1786; and yet when these pieces are ex

posed

produce one hundred to one hundred and ten barrels of turpentine.

Thursday, April 12, 1792. Arrived at Wilmington, North Carolina, about one P. M. Observed on the roads the pitchpines prepared for extracting turpentine, which is done by cutting a hollow in the tree about six inches from the ground, and then taking the bark off from a space of about eighteen inches above it, from the sappy wood. The turpentine runs from April to October, and is caught by the hollow below. Some of the trees were cut on two sides, and only a strip of the bark left of about four inches in breadth on each of the other two sides, for conveyance of the sap necessary for the support of the tree. A captain Cook,. with whom I had been travelling, informed me that some trees would run six or seven years, and that every year the bark was cut away higher and higher, till the tree would run no longer; and I observed many that had done running, and they were in general stripped of the bark on two sides, as high as a man could reach, and some were dead from the opera tion; others did not look much the worse for it. I find the usual task is for one man to attend 3000 trees, which taken together would 1. VOL. LII.

April 15, 1792.

On my return from Wilmington to Cowen's tavern, distant about sixteen miles from thence, I was informed that the master of the house had been a superintendant of negroes who collected turpenI found the information I had before received was not perfectly correct he told me he attended to six slaves for a year for a planter, and between the 1st of April and the 1st of September they made six hundred barrels of turpentine. The cutting the trees for the purpose of collecting is called boxing them; and it is reckoned a good day's work to box sixty in a day. The trees will not run longer than four years; and it is necessary to take off a thin piece of the wood about once a week, and also as often as it rains, as that stops the trees running.

While in North Carolina, I was particular in my inquiries respecting the making tar and pitch, and I saw several tar-kilns; they have two sorts of wood that they make it from, both of which are the pitch-pine. The sort from which most of it is made are old trees, which have fallen down in the woods, and the sap rotted off, and is what they call light wood, not from the weight of it, as it is very beavy, but from its combustible nature, as it will light with a candle, and a piece of it thrown into the fire will give light enough to read and write by. All the pitch-pine will not become lightwood; the people concerned in making tar know it from the apU u pearance

pearance of the turpentine in the grain of the wood. The other sort of wood which is used, after the trees which have been boxed for turpentine have done running, they split off the faces over which the turpentine has run, and of this wood is made what is called green tar, being made from green wood instead of dry.

When a sufficient quantity of wood is got together, the first step is to fix a stake in the ground, to which they fasten a string, and from the stake, as a centre, they describe a circle on the ground according to the size they wish to have the kiln. They consider that one twenty feet in diameter and fourteen feet high should produce them 200 barrels of tar. They then dig out all the earth a spit deep, shelving inwards within, the circle, and sloping to the centre: the earth taken out is thrown up in a bank about one foot and a half high round the edge of the circle. They next get a pine that will split straight, of a sufficient length to reach from the centre of the circle some way beyond the bank this pine is split through the middle, and both parts are then hollowed out; after which they are put together, and sunk in such a way, that one end which is placed in the centre of the circle is higher than that end which comes without the bank, where a hole is dug in the ground for the tar to run into, and whence the tar is taken up and barrelled as it runs from the kiln. After the kiln is marked out, they bring the wood, ready split up, in small billets, rather smaller than are generally used for the fires in. England; and it is then packed as

:

close as possible, with the end inwards, sloping towards the middle, and the middle is filled up with small wood and the knots of trees, which last have more tar in them than any other part of the wood. The kiln is built in such a way, that at twelve or fourteen feet high it will overhang two or three feet, and it appears quite compact and solid. After the whole of the wood is piled on, they get a parcel of small logs, and then place a line of turf, then another line of logs, and so on alternately all the way up, and the top they cover with two or three thicknesses of turf.

After the whole is covered in this way, they take out a turf in ten or a dozen different places round the top, at each of which they light it, and it then burns downwards till the whole of the tar is melted out; and if it burns too fast they stop some of the holes, and if not fast enough they open others, all of which the tarburner, from practice, is able to judge of. When it begins to run slow, if it is near where charcoal is wanted, they fill up all the holes, and watch it to prevent the fire breaking out any where till the whole is charred. The charcoal is worth 2d. to 3d. British sterling, per bushel. It will take six or eight days to burn a tarkiln; in some places they burn it at such a distance from the shipping that they have very far to roll it, and even then sell it at from 3s. 6d. to 5s. British sterling, per barrel, sometimes taking the whole out in goods, but never less than half the amount in goods; from all which it will be reason. ably supposed that tar-burning