N. B. As many of these higher numbers were calculated from Wedgewood's, by the fliding rule, the two or three firft figures only can be depended upon as correct. They will be found however fufficiently accurate for most purposes.

TABLE OF FREEZING MIXTures.

DURING the folution of many faline bodies, a very confiderable reduction of temperature takes place. We fhall extract from Mr. Walker's paper a few of the moft convenient mixtures employed for this purpose.

The falts ought to be recently cryftallized, and reduced to a very fine powder, and the mixture should be made as quickly as poffible. To produce a very great degree of cold, the materials must be previously cooled down by means of other mixtures.

The preceding tables form a part of the late improved edition of the Edinburgh Difpenfatory, edited by Dr. Duncan, jun; to which is added, a fcale for a thermometer, which is perhaps, the most conveniently divided of any other; and which the Editor of the Philadelphia Medical Museum prefumes to defignate by the title of the American Thermometer. These tables as here introduced, form a portion of a new Difpenfatory, now pub lishing here, and which will appear in a few weeks. This, though founded on the bafis of the Edinburgh Difpenfatory, yet as it is entirely on a new plan, the American Editor has ventured to call the American Difpenfatory. A work which has never yet made its appearance here: but the necessity of which has doubtlefs been experienced by every practitioner.

It has unfortunately happened that all the Difpenfatories in common ufe in America, have the formula of both the London and Edinburgh Colleges, which differ in many places from each other, and in fome inftances fo greatly as to be a fource of confiderable difadvantage. Thus, for example, in the formation of antimonial wine, the formula of the London, is double the ftrength of that of the Edinburgh College. This inconvenience is greatly augmented, by the addition of the Dublin Pharmacopoeia, to the late edition of the Edinburgh Difpenfatory, by Dr. Duncan. In Great Britain, this inconvenience is not perceived, because England, Scotland and Ireland, are governed in their prescriptions by the standards of their respective colleges; but in this country, where it is optional with every apothecary to compound his medicines by either Pharmacopoeia, the want of a standard is peculiarly evident. It is of little confequence which fet of formulæ is affumed as a standard, provided it be in general acceptance; and although fuch a publication as is

here proposed to be given to the public, would doubtless appear better under the fanction of the College of Physicians, yet as fuch an event does not appear to be probable; the Editor trufts he will not have performed an useless task in thus advancing as a standard, those formulæ taken from the refpective British Pharmacopoeias, which appeared to him beft. Under this impreffion, he hopes for the aid of his fellow practitioners, in the introduction of the American Difpenfatory; which he is however far from confidering as perfect; yet, from the preceding confiderations, he is impreffed with the belief, that it may be beneficial.

Although the basis of the work is the last edition of the Edinburgh Difpenfatory; the arrangement is fo different from that or any other Difpenfatory the Editor has met with, that he apprehends it may very properly have the diftinctive appellation of the American Difpenfatory. Should the prefent form, &c. be approved by the judgment of the medical world, it will afford the highest gratification to the Editor for the trouble it has given him; and he will cheerfully endeavour from the hints which may be afforded to him, to render any fubfequent edition more perfect than the present.

Memoirs of EDWARD JENNER, M. D. From Dr. LETTSOM'S Oration, delivered before the Medical Society of London, on the 8th of March, 1804.

T

give accurate delineations of living characters is peculiarly difficult. Few can bear the ftern truth of faithfui biography; and where friendship directs the pen, a partiality, of which the writer is, perhaps, unconscious, flides into unmerited panegyric. There are, however, individuals whofe luftre acquires no acceffion from the glow of public gratitude or the ardour of private veneration.-Such is our Jenner, "whom it can never be a degradation to praife, whom it is a degradation to praise without enthusiasm,” the youngest son of the Rev. Stephen Jenner, M. A. of the University of Oxford, Rector of Rockhampton, and Vicar of Berkley, in Gloucesterfhire; at which place Dr. Jenner was born on the 17th day of May 1749.

Befides these church preferments, the refpectable parent poffelfed confiderable landed property in the fame county.

His mother was the daughter of the Rev. Henry Head, of an ancient family in Berkshire; who likewife once held the living of Berkeley, and was at the fame time a Prebendary of Bristol.

Young Jenner loft his father at a very early period of his life; a lofs in fome meafure fupplied by the affectionate attentions of his elder brother, the Rev. John Jenner, B. D. Fellow of Magdalen College, Oxford, united with thofe of another brother, the Rev. Henry Jenner, Domeftic Chaplain to the Earl of Aylesbury, and Vicar of Great Bedwin, Wilts, father