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perature of boiling water is invariable, (while the pressure of the atmosphere remains the same), and the temperature of steam is the same as that of the boiling water from which it escapes.

"But the temperature of boiling water is preferable to all others for making coffee, not only on account of its constancy, but also on account of its being most favourable to the extraction of all that is valuable in the roasted grain. I found that coffee infused with boiling water was always higher flavoured, and better tasted than when the water used in that process was at a lower temperature."

"As all kinds of agitation must be very detrimental to coffee, not only when made, but also while it is making, it is evident that the method formerly practised, that of putting the ground coffee into a coffee-pot with water, and boiling them together, must be very defective, and must occasion a very great loss. But that is not all; for the coffee which is prepared in that manner can never be good, whatever may be the quantity of ground coffee that is employed. The liquor may no doubt be very bitter, and it commonly is so; and it may possibly contain something that may irritate the nerves, but the exquisite flavour and exhilarating qualities of good coffee will be wanting.".

"Coffee may easily be too bitter, but it is impossible that it should ever be too fragrant. The very smell of it is reviving, and has often been found to be useful to sick persons, and especially to those who are afflicted with violent head-achs. In short, every thing proves that the volatile, aromatic matter, whatever it may be, that gives flavour to coffee, is what is most valuable in it, and should be preserved with the greatest care, and that, in estimating the strength or richness of that beverage, its fragrance should be much more attended to, than either its bitterness or its astringency."

"One pound averdupois, of good Mocha coffee, which, when properly roasted and ground, weighs only fourteen ounces, serves for making fifty-six full cups of the very best coffee, in my opinion, that can be made.

"The quantity of ground coffee which I use for one full cup, is 108 grains troy, which is rather less than a quarter of an ounce. This coffee, when made, would fill a coffee-cup of the common size, quite full; but I use a larger cup, into which the coffee being

poured boiling hot, on a sufficient quantity of sugar (half an ounce), I pour into it about one-third of its volume of good sweet cream, quite cold. On stirring these liquids together, the coffee is suddenly cooled, and in such a manner as not to be exposed to the loss of any considerable portion of its aromatic particles in that process.

"In making coffee, several circumstances must be carefully attended to in the first place, the coffee must be ground fine, otherwise the hot water will not have time to penetrate to the centres of the particles; it will merely soften them at their surfaces, and, passing rapidly between them, will carry away but a small part of those aromatic and astringent substances on which the goodness of the liquor entirely depends. In this case, the grounds of the coffee are more valuable than the insipid wash which has been burried through them, and afterwards served up under the name of coffee.

"As a gill is a measure well known in England, I shall adopt it as a standard measure for a cup of coffee; and as it is inconvenient to fill coffee-cups quite full to the brim, I shall propose coffee-cups to be made of the form and dimensions they now commonly have, or of a size proper for containing 8 1-3d cubic inches of liquor, when filled quite full to the brim. I have found by the results of a great number of experiments, that one quarter of an ounce avoirdupois of ground coffee is quite sufficient to make a gill of most excellent coffee, of the highest possible flavour, and quite strong enough to be agreeable.

"Formerly, the ground coffee being put into a coffee-pot, with a sufficient quantity of water, the coffee-pot was put over the fire, and after the water had been made to boil a certain time, the coffee-pot was removed from the fire, and the grounds having had time to settle, or having been fined down with isinglass, the clear liquor was poured off, and immediately served up in cups.

"From the results of several experiments which I made with great care, in order to ascertain what proportion of the aromatic and volatile particles in the coffee escape, and are left in this process, I found reason to conclude, that it amounts to considerably more than half.

"When coffee is made in the most advantageous manner, the ground coffee is pressed down in a cylindrical vessel, which has its

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bottom pierced with many small holes, so as to form a strainer; and a proper quantity of boiling hot water being poured cautiously on this layer of coffee in powder, the water penetrates it by degrees, and after a certain time begins to filter through it. This gradual percolation brings continually a succession of fresh particles of pure water into contact with the ground coffee; and when the last portion of the water has passed through it, every thing capable of being dis. solved by the water will be found to be so completely washed out of it, that what remains will be of no kind of value.

"It is however necessary to the complete success of this ope. ration, that the coffee should be ground to a powder sufficiently fine.

"In order that the coffee may be perfectly good, the stratum of ground coffee, on which the boiling water is poured, must be of a certain thickness, and it must be pressed together with a certain degree of force. If it be too thin, or not sufficiently pressed together, the water will pass through it too rapidly; and if the layer of ground coffee be too thick, or if it be too much pressed together, the water will be too long in passing through it, and the taste of the coffee will be injured.

The author recommends as of importance that the surface of the coffee be rendered quite level after it is put into the strainer, before any attempt is made to press it together, that the water in percolating may act equally on every part. For this purpose he uses the following contrivance : "The circular plate of tin, with a rod fastened to its centre, which serves as a rammer for pressing down the ground coffee, has four small projecting square bars, of about one-tenth of an inch in width, fastened to the under side of it, and extending from the circumference of the plate to within about one quarter of an inch of its centre. On turning this plate round its axis, by means of the rod which serves as a handle to it, (the rod being made to occupy the axis of the cylindrical vessel,) the projecting bars are made to level the ground coffee; and after this has been done, and not before, the coffee is pressed together.

"This circular plate is pierced by a great number of small holes, which permit the water to pass through it, and it remains in the cy lindrical vessel during the whole of the time that the coffee is making, It reposes on the surface of the ground coffee, and prevents its being thrown out of its place by the water which is poured on it. The

rod which serves as a handle to this circular plate is so short, that it does not prevent the cover of the cylindrical vessel from being put down into its place."

Two-thirds of an inch answers best for the coffee in powder before it is pressed together, and the pressure should be such as to reduce the thickness to something less than half an inch.

"A Table, showing the diameters and heights of the cylindrical vessels (or strainers) to be used in making the following quantities of coffee :

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As these heights are nearly equal, the Count recommends that the strainers be all made of the height of 5 inches, and suspended in their reservoir at such a height that their bottoms be above the percolated fluid when all has passed through.

"The reservoir and its boiler, he then observes, must be soldered together above, at their brims; and the reservoir must be suspended in its boiler, in such a manner that its bottom may be about a quarter of an inch above the bottom of the boiler.

"The small quantity of water which it will be necessary to put into the boiler, in order that the reservoir for the coffee may be surrounded by steam, may be introduced by means of a small opening on one side of the boiler, situated above, and near the upper part of its handle.

"The spout through which the coffee is poured out passes through the side of the boiler, and is fixed to it by soldering. The cover of the boiler serves at the same time as a cover for the reservoir, and for the cylindrical strainer; and it is made double, in order more effectually to confine the heat.

"The boiler is fixed below to a hoop, made of sheet-brass, which is pierced with many holes. This hoop, which is one inch in width, and which is firmly fixed to the boiler, serves as a foot to it when it

is set down on a table, and it supports it in such a manner that the bottom of the boiler is elevated to the height of half an inch above the table.

"When the boiler is heated over a spirit lamp, or over a small portable furnace in which charcoal is burnt, as the vapour from the fire will pass off through the holes made in the sides of the hoop, the bottom of the hoop will always remain quite clean, and the table. cloth will not be in danger of being soiled when this coffee-pot is set down on the table.

"As the hoop is in contact with the boiler, in which there will always be some water, it will be so cooled by this water as never to become hot enough to burn the table-cloth.

"The bottom of the boiler may be cleaned occasionally, on the underside, with a brush or a towel; but it should not be made bright; for when it is bright it will be more difficult to heat the water in it than when it is tarnished and of a dark-brown colour.

"But the sides of the boiler should be kept as bright as possible; for, when its external surface is kept clean and bright, the boiler will be less cooled by the surrounding cold bodies, than when its me. tallic splendour is impaired by neglecting to clean it*.

"As the small quantity of water which is put into the boiler serves merely for generating the steam which is necessary in order to keep the reservoir and its contents constantly boiling-hot; if the reservoir be made of silver, or even of common tin, the boiler may, without the smallest danger, be made of copper; or of copper plated with silver, which will give to the boiler an elegant appearance, and at the same time render it easy to keep it clean on the outside.

"The boiler may likewise be made of tin, and neatly japanned on

I have in my possession two porcelain tea-pots, of the same form and dimensions, one of which is gilt all over on the outside, and might easily be mistaken for a gold tea-pot; the other is of its natural white colour, both within and without; being neither painted nor gilt. When they are both filled at the same time with boiling water, and exposed to cool in the same room, that which is gilt retains its heat half as long again as that which is not gilt. The times employed in cooling them a given number of degrees, are as three to two.

"The result of this interesting experiment (which I first made about seven years ago) affords a good and substantial reason for the preference which English ladies have always given to silver tea-pots. The details of this experiment may be seen in a paper published in the Memoirs of the French National Institute for the year 1807."

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