into alburnum, as has been generally believed by preceding naturalists. More experiments are obviously wanted to determine this point.

VII. Some account of Cretinism. By Henry Reeve, M. D. of Norwich. Read, Feb. 11. 1808.

Cretinism, a term, the derivation of which we have not traced, is used to denote a species of mental imbecility, found not only in the vallies of the Alps, but in the mountainous parts of Germany and Spain. This disorder prevails in all the intermediate degrees from excessive stupidity to complete fatuity. The enlargement of the thyroid gland, called goitre, is usually the most striking feature in the appearance of a cretin: his head also is deformed; his stature diminutive; his complexion sickly; his countenance vacant; his lips and eyelids coarse and prominent; his skin wrinkled and pendulous; his muscles loose and flabby. Dr. Reeve's account of this dismal malady is interesting; but it throws little if any new light upon the subject; we shall not, therefore, make any quotation from this paper, but shall only observe that filth, confinement, the bad quality of the air and food, and the neglect of moral education, which attach to poverty in certain situations, are considered as producing cretinism; that the common idea of its originating in the use of snow water is exploded for good reasons; and that as far as Dr. Reeve observed, the parents of the unfortunate being, instead of taking any pride in having any of their children ideots or bien-heureux, as some authors have asserted, were very much ashamed to acknowledge the fact.

VIII. On a new Property of the Tangents of the three angles of a plane Triangle. By Mr. William Garrard, Quarter Master of Instruction at the Royal Naval Asylum at Greenwich. Communicated by the Astronomer Royal. Read, Feb. 11.

1808.

IX. On a new Property of the Tangents of three Arches, trisecting the Circumference of a Circle. By Nevil Maskelyne, D. D. F. R. S., and Astronomer Royal. Read, Feb. 18, 1808.

The property mentioned by Mr. Garrard, is, that the sum of the tangents of the angles of a plane triangle, multiplied by the square of the radius, is equal to the continued product of those tangents. The property mentioned by Dr. Maskelyne, is a very natural and obvious extension of Mr. Garrard's: viz. The sum of the tangents of three arches any way trisecting a circle, multiplied by the square of the radius, is equal to the product of those tangents.

Mr. Garrard's demonstration is rather clumsy; and is divided into two cases, one applying to the instances of acute

angled, the other to those of obtuse angled, plane triangles. The Royal Astronomer's demonstration, when freed from an obvious inadvertency into which he has fallen, is simple and satisfactory.

It behoves us to remark, that the new property' of tangents, here spoken of, is not even newly discovered. It has been well-known to most mathematicians for at least half a century, and was indeed proposed by this identical Quartermaster Garrard more than nineteen years ago, in a little periodical work called the Scientific Receptacle,' published by Longman and Co. At that time, we conjecture, Mr. Garrard might not be able to demonstrate the property, simple as it is; for, though there are four demonstrations of the theorem in the Scientific Receptacle, not one of them is his! In the course of nineteen years, however, the Quarter-Master of Instruction' contrives to manufacture a demonstration out of the four that had been published, somewhat different from any of them; and has the luck to foist property and demonstration upon the Astronomer Royal as new. We are not surprized that Dr. Maskelyne should be imposed upon; because we know his kindness and condescension will induce him to encourage whatever and whomsoever he thinks ingenious; and because it is natural that at his time of life he should have forgotten much more than ever Mr. Garrard learnt, still retaining just claims, however, to an immeasurably higher rank. But that those members of the Royal Society, whose business it is to determine what papers shall be inserted in their Transactions, should be so ignorant of the real state of the mathematical sciences, as to publish for new theorem so well known, is to us, and doubtless to all mathematicians at home and abroad who have seen these two articles, perfectly astonishing!

a

X. An Account of the Application of Gas from Coal to Economical Purposes. By Mr. William Murdoch. Read, Feb. 25. 1808.

the

Mr. Murdoch here claims as his own the first idea of applying gas from coals to economical purposes, as a substitute for the light furnished by oil and tallow; and also the first actual application of the gas. He very candidly and modestly mentions the circumstance of Dr. Clayton's knowledge of the inflammable property of the gas, so long back as 1739, (See Phil. Trans. vol. xli.) as well as that of the current of gas, escaping from Lord Dundonald's tar ovens, being frequently fired but says he was unacquainted with these particulars when he commenced his experiments at Redruth in Cornwall about sixteen years ago. He traces the progress of his reflections and experiments on this curious topic from that period to the present; but dilates chiefly upon observations

made during the winter of 1807, at the cotton manufactory of Messrs.Philips and Lee, at Manchester, where the light obtained by the combustion of the gas from coals is used upon a very large scale. We shall make one or two such quotations from this paper, as will tend to shew the advantages that may result from the introduction of gas lights under favourable cir

cumstances.

It is not my intention, in the present Paper, to enter into a particular description of the apparatus employed for producing the gas; but I may observe generally, that the coal is distilled in large iron retorts, which during the winter season are kept constantly at work, except during the intervals of charging; and that the gas, as it rises from them, is conveyed by iron pipes into large reservoirs, or gazometers, where it is washed and purified, previous to its being conveyed through other pipes, called mains, to the mill. These mains branch off into a variety of ramifications (forming a total length of several miles), and diminish in size, as the quantity of gas required to be passed through them becomes less. The burners, where the gas is consumed, are connected with the above mains, by short tubes, each of which is furnished with a cock to regulate the admission of the gas to each burner, and to shut it totally off when requisite. This latter operation may likewise be instantaneously performed, throughout the whole of the burners in each room, by turning a cock, with which each main is provided, near its entrance into

the room.

The burners are of two kinds; the one is upon the principle of the ARGAND lamp, and resembles it in appearance; the other is a small curved tube with a conical end, having three circular apertures or perforations, of about a thirtieth of an inch in diameter, one at the point of the cone, and two lateral ones, through which the gas issues, forming three divergent jets of flame, somewhat like a fleur-de-lis. The shape and general appearance of this tube, has procured it among the workmen, the name of the cockspur burner.

The number of burners employed in all the buildings, amounts to 271 ARGANDS, and 633 cockspurs, each of the former giving a light equal to that of four candles of the description abovementioned; and each of the latter, a light equal to two and a quarter of the same candles; making therefore the total of the gas light a little more than equal to that of 2500 candles. When thus regulated, the whole of the above burners require, an hourly supply of 1250 cubic feet of the gas produced from cannel coal: the superior quality and quantity of the gas produced from that material having given it a decided preference in this situation, over every other coal, notwithstanding its higher price.' pp. 125, 126.

Cost of 110 tons of cannel coal, 1251. Cost of 40 tons of common coal, 20.=145. Deduct the value of 70 tons of coak, 93. The annual expenditure in coal, after deducting the value of the coak, and without allowing any thing for the tar, is therefore, 521. And the interest of capital, and wear and tear of apparatus, 5501; making the total expence of the gas apparatus, about 6001. per annum.

That of candles, to give the same light, would be about 20001. For each candle consuming at the rate of 4-10ths of an ounce of tallow per hour, the 2500 candles burning upon an average of the year two

hours per day, would, at one shilling per pound, the present price, amount to nearly the sum of money abovementioned,

"If the comparison were made upon an average of three hours per day, the advantage would be still more in favour of the gas light; the interest of the capital, and wear and tear of the apparatus continuing nearly the same as in the former case: thus,

• 1250 × 3 = 3750 cubic feet of gas per day, which would be preduced by 104 cwt. of cannel coals; this multiplied by the number of working days, gives 168 tons per annum, which, valued as before, amounts to 1881. And 60 tons of common coal, for burning under the retorts, will amount to 301.2181. Deduct 105 tons of coak at 26s. 8d. 1401. Leaving the expenditure in coal, after deduction of the coak, and without allowance for the tar, at 781. Adding to which the interest and wear and tear of apparatus, as before, the total annual cost will not be more than 6501. whilst that of tallow, rated as before, will be 30001. pp. 128, 129.

If the comparison, however, were made with oils, the advantages, as Mr. M. frankly acknowledges, would be less than in the comparison with tallow. Still, they will at any rate be very considerable: and therefore, as this method of lighting manufactories where there are combustible materials is less dangerous than lighting either by candles or by lamps, we hope it will experience a more extensive trial.

:

A certain Mr. F. A. Winsor has for the last three or four years been striving hard to amuse the public, with some of the most extravagant proposals that ever emanated from any head which was not as light as though its brains were converted into gas it will be seen from what is here related, that, even if Mr. Boyle had not in 1691, and Dr. Clayton in 1739, discovered the inflammability of the gas from coals, Mr. Winsor is completely anticipated, both as to the discovery and as to the practical application of it, by Mr. Murdoch. But, instead of exposing further the ridiculous pretensions of this Mr. Winsor, we shall briefly describe the methods by which a far more ingenious patentee, Mr. Edward Heard, proposes to prevent the disagreeable and noxious effects of the gas. In the first of these, Mr. H. stratifies the coals with lime, in the retort, or other vessel in which they are distilled: In the second, the gas produced from coals distilled per se is passed over lime contained in a heated tube. After the gas has been conducted into a refrigeratory, and all the condensible vapour has been deposited, it is burned in the usual

manner.

Some farther experiments on the uses of coal gas for manufactories, &c. by Mr. B. Cook of Birmingham, are described in Nicholson's Journal, vols. 21, 22, and nos. 25, 27, of the Athenæum; to which we must refer those of our readers to whom this inquiry is interesting; as we have already far over.

stepped the limits we originally assigned to the present ar ticle.

This Part of the Transactions contains the Meteorological Register of the Royal Society, for 1807. We observe in it nothing remarkable, except that the variation, or, as we should prefer calling it, the declination, of the magnetic needle, is stated to be 24° 10',2 for September. Why is the declination recorded for June 1806, and for September 1807? The observations of Canton, of Gilpin, and of others, shew very decidedly that the declination varies at different seasons of the year; so that we should expect to find it exhibited for every month, if not for every day, in the R. S.'s Meteorological Register. No such thing, however, is done: but rather, as if for the express purpose of preventing comparison, the declination for one year is shewn at the summer solstice, and for the succeeding year at the autumnal equinox!

Art. V. An Etymological Dictionary of the Scottish Language: illustrating the Words in their different Significations, by Examples from ancient and modern Writers; shewing their affinity to those of other Languages, and especially the northern ; explaining many terms, which, though now obsolete in England, were formerly common to both Countries; and elucidating National Rites, Customs, and Institutions, in their analogy to those of other Nations: to which is prefixed, a Dissertation on the Origin of the Scottish Language. By John Jamieson, D. D. Fellow of the Royal Society of Edinburgh, and of the Society of the Antiquaries of Scotland. 4to. 2 vols. pp. 1300 price 47. 4s. bd. Edinburgh, Creech, Constable; Longman and Co. Cadell and Co. 1808.

A CONTINUANCE of distinctions in language, among

people who are mingled in the same country and live under the same government, is by no means to be wished. They interrupt that freedom and familiarity of intercourse which the interests of commerce demand, and, like the ruins of old entrenchments and barriers, serve to perpetuate the feelings of reciprocal fear and enmity. It is extremely desirable, however, for the purposes of history, that these monuments of ancient discord should not be entirely obliterated. Dictionaries may be considered as bearing some analogy to the drawings of these decayed antiquities; and, like them, are of inestimable worth to the antiquary, and the historian, without obstructing the progress of national improvement or the extinction of ancient feuds. They are not less valuable to the philologist, who inves tigates the language, and the philosopher who studies the literature of distant ages.

It is more a subject of regret, however, than of surprise, that no Scotish antiquarian, previous to the anthor now before us, has attempted to rescue the language of his country from obli