Art. 39. Dialogues of the Dead with the Living. 8vo. 4s. Boards. Conant, &c. 1779.

In thefe Dialogues, Lord Herbert is conjured up from the vafty deep,' to read his own recantation of his errors, and to perfuade David Hume to do the fame-Shakespeare revifits the glimpses of the moon,' to give Garrick an opportunity of faying, " Angels and minifters of grace defend us," to praise his merits and reprove his faults, and to cenfure him for making his favourite poet the god of his idolatry' in the Stratford jubilee.-Fielding pays his compliments to Mr. Courtney Melmoth, to whisper in his ear, that he poffeffes an everflowing vivacity, and a fund of genuine wit, which only require that they fhould be chaftened by religion, and curbed by judgment, to render him a moft agreeable writer: that his heart is good, his wit flowing, his language elegantly exprefive; his painting the work of a mafter, and his powers in the pathetic, fuch as to make every fibre of the finer affections vibrate; that his Pupil of Pleafure is in its defign great and good, and merits the warmest thanks of the friends of virtue-[Oh fie, Mr. Ghoft! furely not!] and that he bids fair to be one of the first writers of the age [0 tempora!]-Sherlock leaves the manfions of the bleffed to upbraid Jenyns with infincerity, and to accufe him of arguing weakly with defign, of treating Chriftianity with coldness and levity, and of throwing out infinuations unfriendly to the Chriftian caufe.-Cowley lays afide his feraphic lyre to reprove Dr. Hurd for publishing a mutilated edition of his works —Mr. Addison fteals into the closet of Dr. Johnson, to give him a gentle rebuke, for rambling into the thorny paths of party, and to hint to him, that his writings would be more pleafing, if he would alter the uncouth drefs of his expreffions, and polish the rugged severity of his thoughts.'-The venerable Langton fternly reproaches the courtly Gibbon with having reprefented the Church as unfriendly to the rights of the people, and unjustly depreciated the Chriftian religion; and to affure him that in the world of fpirits, all believe.' And lastly, Cicely, Duchefs of York, does penance for her pride and ambition, by prefenting herself before Lady S. to give an unwilling teftimony to her uncommon merit.

In all this, there is neither argument enough to carry much conviction, nor wit enough to afford much entertainment.-Let this fhort outline of these Dialogues then fuffice.

MEDICA L.

Art. 40. A Review of Dr. Lettfom's Obfervations on Baron Dimfdale's Remarks refpecting Dr. Lettfom's Letter on General Inoculation. By the Hon. Baron T. Dimsdale. 8vo Pamphlet. Owen, &c.

1779.

We took the liberty of declaring, with refpect to the piece to which this is an answer, that the disagreeable difpute between these ingenious doctors being now become entirely perfonal, we looked upon ourselves as excufed from entering at all into its merits. On this account, we only notify the publication of the prefent reply, for the information of thofe of our Readers who may be inclined to examine both fides of the question.

SERMON.

SERM O N.

Preached in the Parith Church of St. Matthew, Bethnal Green, November 22, 1778. For the Benefit of the Charity Children of the faid Parish. By Samuel Beazville, A. B. Minister of the French Church in St. John Street in the faid Parish. 8vo. Fry, &c.

It is impoffible to read this plain and well-adapted fermon without heartily withing that the defign of its publication may be fully an fwered. There are fome inaccuracies in it, with refpect to ftyle, but thefe are well compenfated by the pious, grateful, and benevolent fpirit of the Preacher.

IN

CORRE

S.PONDENCE.

To the REVIEWERS.

N the year 1775 came out a publication, entitled," Advice from a Father to a Son, just entered into the Army, and about to go abroad into Action; in Seven Letters." I do not remember to have feen it taken notice of by you; and as they have great merit, both for the advice they inculcate, and the manner in which they are written, you would greatly oblige one of your Readers if you could inform him who was their Author, and whether they were written from a father to a fon in the circumstances therein mentioned. OXONIENSIS.

Oxonienfis will find an account of the tract which he speaks of, in our Catalogue for October, 1776, Art. 28. We commended the performance, but of the Writer we are entirely ignorant.

A very fenfible Correfpondent, who figns D. D. has favoured us with a friendly admonition, on account of what he deems an illiberal and uncandid reflection on the courts of France and Spain; vid. our latt Appendix, p. 5:6, 557. The Author of that Article, (one of our Foreign Correspondents) not being in England, has no immediate opportunity of replying to what D. D. has objected against the paffage in queftion; nor do we pretend to juftify even the falleft appearance of local prejudice or vulgar attachment.-But it is difficult for a "True-born Englishman" to confine himself within the bounds of politenefs, when the machinations of thofe who are the avowed enemies of his country, are prefented to his obfervation.-If this apology is not deemed fufficient, we muft fubmit to the cenfure of the candid Public.

tt Some jutt remarks of this Correfpondent on National Perfidy, &c. will, probably, be, hereafter, adverted to: they are too good to be luit.

We are much obliged by the letter figned Z. 2; but it came to hand too late for more particular acknowledgement in this Month's Review. It will, however, furnish a paragraph for the last page of our next Number.

The Canadian Freeholder, Vol. II. the Conclufion of our account of Dr. Priestley's Experiments and Obfervations, and The Modern Hiftoryof Europe, will be inferted in our next.

THE

MONTHLY REVIEW,

For SEPTEMBER, 1779.

ART. I. Experiments and Obfervations relating to various Branches of Natural Philofophy, &c. By Jofeph Priestley, LL.D. F. R. S. [Concluded from our Review for June laft, pag. 441.]

HE difcoveries and new obfervations relating to dephlogifTticated air, contained in this volume, are too numerous

and important not to require particular confideration. We shall accordingly, in this concluding Article, almoft wholly confine our attention to this interefting fubject.

In our account of the Author's fecond volume of Obfervations on Air [See Monthly Review, February, 1776, p. 108] we related, pretty much at large, the fteps by which Dr. Priestley was led to this memorable difcovery. From that account it ap pears that he obtained dephlogifticated air from mercurius calcinatus, and red lead, by mere heat, and which they must have attracted from the atmosphere during their calcination. He af terwards found that dephlogisticated air was producible from combinations of the nitrous acid with any kind of earth whatever. The trials which he had then made with the vitriolic and marine acids, under fimilar circumftances, not having been attended with the production of this kind of air, he was naturally led to conclude that the nitrous acid was an effential or neceffary ingredient in the process.

At the time of the Author's laft philofophical publication, he did not, nor could he reasonably, fufpect that fubftances buried in the bowels of the earth, where no nitrous acid is known, or even fufpected, to exift, and which cannot be fuppofed, in that fituation, to have attracted air from the atmofphere, fhould nevertheless furnish dephlogifticated air, merely by the affiftance of heat, or without the addition of nitrous acid. In a courfe of experiments, however, made only with a view to discover what kind of air, and in what proportion, certain mineral fubftances would yield, on being expofed to a red heat; ... Vo L. LXI.

M

he

he had the following refults, on fubjecting the mineral fubftance called Manganefe to this new mode of analyfis.

On putting an ounce of this fubftance into a small retort with a very long and narrow neck, and expofing it to a red fand heat, forty ounce measures of air were expelled from it in different portions. Part of this air, in every portion, was fixed air, and at first almoft wholly fo: but four-fifths of the last produce was the pureft dephlogisticated air. He was naturally much furprised at this refult; as the cafe does not appear reducible to either of those recited at the beginning of this Article: for here no nitrous acid had been employed; nor had the fubftance, till it was dug out of the bowels of the earth, been exposed to the influence of the atmosphere :-unless indeed we recur to fome unknown and very distant æra, in which it may poffibly have had a communication with the external air, and have acquired its dephlogifticated air, in a manner fimilar to that in which the precipitate per fe, and red lead, at prefent acquire their pure air, during the act of calcination, in our laboratories. According to this idea, we may say that manganefe (the nature of which is very little known) may probably be a metallic calx, which has undergone a calcination in volcanos, long fince extinct; but which may formerly have had a communication with the atmosphere. We fcarce need to add, that on re-calcining this calcined manganefe, moiftened with the nitrous acid, more fixed air, and pure or dephlogisticated air, were produced.

The Author fubjected likewife an ounce of lapis calaminaris to a red heat, without addition; and expelled from it about 316 ounce measures of air, the whole of which, however, was fixed air, except four ounce meafures, which appeared to be nearly as good as common air.

In the course of these experiments, and afterwards, in conformity with a communication from Signor Landriani, the Author found that the prefence of nitrous acid, qua nitrous acid, was not neceffary to the production of dephlogifticated air from combinations of metallic earths with mineral acids. While he was pursuing this train of experiments, he found this kind of air produced from green vitriol, and likewife from the blue and white vitriols. Sufpecting however the purity of the vitriols of the shops, which might have acquired fome mixture of fpirit of nitre, he prepared fome green vitriol himself, by diffolving clean iron filings in oil of vitriol diluted with water. Diftilling the matter in a retort, he had the fame refults as in his preceding experiments: the dephlogisticated air which came over laft being very turbid, and exceedingly pure.

He now fufpected the purity of his oil of vitriol, which, at prefent, is generally procured from fulphur with the addition of nitre. He therefore next employed the vitriolic acid prepared

in Newmann's manner, in which no nitre is used: but dephlogifticated air was ftill produced from the combination of iron filings with this purer acid. And left the mixture of these two fubftances might be fufpected to have attracted pure air, in confequence of their expofure to the atmosphere, during their combination, he conducted the experiment in the following fcrupulous manner :

He diffolved five pennyweights one grain of iron in a fufficient quantity of pure oil of vitriol, which had been carefully prepared for this purpose by Mr.Winch, so as to be free from any admixture of the nitrous acid. The diftillation was performed in the very fame retort in which the folution had been made, and in the continuation of the fame procefs; fo that all communication with the external air was moft effectually precluded.

Conducting the process, with these attentions, and distilling the folution to drynefs, in a long necked retort, the fucceeding products were, first, the common air a little phlogifticated, and then a little fixed air, and much vitriolic acid air; and lastly 18 ounce measures of dephlogisticated air. The refiduum, or ochre, ftill weighed more than the iron filings originally employed; fo that it probably retained a quantity of the oil of vitriol, and had the heat been increased, more air might yet have been procured.

Adding fresh oil of vitriol to this refiduum, and treating it as before, but in a gun-barrel, a ftill larger quantity of dephlogifticated air was produced: fo that the oil of vitriol appeared capable of generating dephlogisticated air, on its admixture with iron, toties quoties, as well as the nitrous acid with red lead and other substances, in the Author's former experiments. In fact, it now appears that he had formerly produced dephlogisticated air from compounds containing the vitriolic acid, particularly blue vitriol and alum, in a very early ftage of his trials: though at that time he was totally ignorant of its nature. [See his first volume of Observations, page 155, and Vol. II. page 86.]

A combination of the vitriolic acid with mercury likewile furnished the Author with a notable quantity of dephlogisticated air. For on diftilling, in a grzen glafs retort, an ounce of pure quickfilver diffolved in vitriolic acid; though fome of the matter was loft, by the breaking of the retort, yet on exposing it, in a fresh retort, to a red heat, he got from it, after the expulfion of a great quantity of vitriolic acid air, and fixed air, about 50 ounce meafures of dephlogifticated air. More dephlogifticated air was afterwards procured, on expofing to the heat a fecond time the white matter which had fublimed into the neck and fides of the retort.