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Befide the advantage of deftroying infects, the fuds appear to be productive of other good effects. When applied just after the fall of the leaf, they contribute much to preserve the wood of the delicate and tender kinds of peaches. I account for it thus: It is allowed that our fummers are, in general, too short to perfect the wood of the tender kinds of peach and nectarine trees without artificial means, and when the wood of these trees is imperfectly ripened, it is very fubject to the canker, especially if, in the fucceeding winter, there happens a fucceffion of rain and froft. This the nurseryman, as well as the gardener, often woefully experiences.

I conftantly have obferved that the canker originates at, or clofe adjoining to, the buds of the laft year's wood. The caufe feems to be this. Wood imperfectly ripened is always foft and spongy, and therefore admits of imbibing a large por tion of moisture in rainy weather. The bud and the fine capillary veffels adjoining it being furcharged with moisture in a wet evening, when the froft comes at night, it freezes the moisture in the veffels, and caufes it to expand; which, by tearing the veffels afunder, brings on a decay of the parts. Now the foap-fuds feem to leave a gloffy kind of coat or covering on the branches, and the oily particles contained in the fuds, by penetrating them, prevent their being overcharged with moisture.

But here it may feem ftrange that oil fhould act this friendly part, when it is well known to be fo highly pernicious to plants in general. That it is fo, in its genuine ftate, is proved by daily experience. The general and received opinion of wool being poisonous to plants, is from no other cause than

from the oil contained in it.

• But notwithstanding that oil has this pernicious effect on plants, when in its original and genuine ftate, ftill, when made mifcible, perhaps nothing is more nourishing and friendly to them. This brings me to confider foap-fuds as a manure to the borders, for it is evident that by the rains and dews, the principal of it does terminate there at laft; and this important confideration alone is fufficient to recommend the practice. It may feem unneceffary to obferve, that foap-fuds contain a larger portion of oily particles after a common wafhing, than in the original state.

I fhall conclude this digreffional note with obferving, that foap-fuds keep trees clear of mofs, and render the bark clear and healthy.'

The branch of gardening which has of late received the greatest improvements, is that which relates to the management of hot-houses, hot-walls, and hot-beds. A general treatife on thefe fubjects, explaining the particular modes of cultivating the various plants that are raifed or brought to perfection by

thefe

thefe artificial methods, would be a valuable acquifition to the gardener's library. It is needlefs to fay by whom we wish to fee it executed.

ART. VI. Observations on the Doctrine laid down by Sir William Blackstone refpecting the Extent of the Power of the British Parliament, particularly with relation to Ireland. In a Letter to Sir William Blackftone; with a Poftfcript addreffed to Lord North, upon the Affairs of that Country. 8vo. I s. 6d. Almon. 1779.

WE

E have fuffered this pamphlet to flumber peaceably on our shelf beyond the time in which we generally announce political publications, because we apprehended that it turned lefs on political than on legal topics, and because we confider that law will, in general, keep longer than politics, which are of a more fleeting and tranfitory nature. On a more attentive perufal, however, of the arguments it contains, we are rather inclined to clafs it under the latter defcription.

Though we entertain no doubt that this publication comes from a lawyer's pen, it will be found that the pofitions which Sir William Blackftone has advanced, and which this Writer has chosen to difcufs, are independent of legal inferences, and admit of little legal controverfy. Our laws certainly acknowledge no higher authority than that of parliament. Here refides the abfolute power of "making, confirming, enlarging, restraining, abrogating, repealing, reviving, and expounding laws concerning matters of all poffible denominations, ecclefiaftical or temporal, civil or military, maritime or criminal." Whatever epithet be thought defcriptive of this high power, it cannot alter its effential properties; much less can its existence be difproved by afferting a poffibility of its being abused. If Sir William Blackstone, in difplaying its nature and extent with a laboured pomp of words, has unfortunately provoked this Writer's fpleen, we muft obferve that the learned Commentator is fafely entrenched behind the authority of the most respectable Whigs, and warmeft admirers of the conftitution. It is an inftance of the caprice of all fublunary things, that the fame language which was popular in one age becomes in another fufpected and obnoxious. In the last century, the power of parliaments was the palladium of English liberty, and the favourite. theme of Englishmen. It was not imagined that a parliament could ever be faithlefs to the interefts of the people, and therefore the conftitution has not provided any check in such a cafe, beyond the ordinary remedy placed in the hands of the elective. body, on every new election of reprefentatives. A change of fituation may, no doubt, induce a change of language, along

Black. Comm, Book I. C. 2.
A 2 4

with

with a change of doctrine; but they who adhere to the old ought not to incur the cenfure of thofe who adopt new systems or opinions. There is fo much wisdom difplayed in the frame of our government, and the different parts of legiflation are adjufted to each other with fuch a happy nicety, that the highest encomiums will not feem hyperbolical. They who wish to fee it perpetuated, can hardly be blackened by all the eloquence, and more than all the argument which this Gentleman has employed against Sir William Blackstone. We trust the people of this country will always have fenfe to feel, and fpirit to defend their rights, under whatever forms the attack may be mafqued. But if ever they should be fo far exafperated at the conduct of their parliaments, as to ftrike them out of the book of politicaļ life; what they would gain by fuch a revolution is rather matter of experiment than of theory. Whether the conftitution would be reformed, or whether it would be fubverted, is an ar duous point, at which the wifeft men may well paufe, and about which the most patriotic may be divided. The Commentator on the Laws of England has a right to pronounce bis opi nion, and may furely be pardoned for venturing to affirm, that as long as the English conftitution lafts, the power of parliament is abfolute, and without controul." The motives, however, on which he is fuppofed to have efpoufed this doctrine, are difcovered by our Letter-writer with a great deal of goodnatured penetration. "You and I, Sir William, know, that the doctrine of the omnipotence of parliament is a very favourite one in the quarter of promotion: and it was very natural you fhoul prefer a feat on the woolfack to one in the House of Commons." This is one of the triteft artifices of controverfy Sir William Blackstone is here accused of a base and infamous defign to mislead the understandings of his countrymen, on the most important of all fubjects, merely because it gives spirit and poignancy to the flyle of a difputant to fuppofe it as if to confute a man's arguments it was neceffary to wound his character, We are more furprised to find occafion for this remark given by a writer of learning and genius (for fuch the Author of this letter difcovers himself to be), as he appears to us to have gone out of his way to make the attack. His favourite object, which is to prove the independency of the Irifh parliament, ftands clear of this part of the learned Commentator's pofitions. He might have admitted, confiftently with the tenor of his arguments, that the power of the English parliament is fupreme and unbounded within this kingdom (as invefted with all the powers which the community it reprefents can beftow), and at the fame time have denied, as he afterwards does, its legiflative power over a different community which has a parliament of its own. This latter pofition he endeavours to establish by a long and

elaborate

elaborate investigation of the principles of government; but the fubject has been fo completely exhaufted in the American controverfy, that we find no new light here thrown upon it.-Mr. Burke tomewhere fays, that "it is not eafy to make a monopoly of theorems and corollaries:" The Irifh are too quickfighted not to perceive that the arguments employed by America are ready made to their hands; and if they do not apply them to their own cafe, it certainly is not the fault of their writers. Among the able advocates that have started up in their caufe, what precife degree of rank and eftimation the Author of this pamphlet may have obtained, we are not fufficiently informed to pronounce t. Whether he be the firft in point of popularity or not, he has a claim on the national gratitude, as first in the order of time; having appeared in print before the letters figned Guatimozin, and other popular publications, forced themfelves into notice. We lament the mistake which has fo long poftponed our account of his performance,

We have heard this publication afcribed to Ch―s F Sh-d-n, Efq.

ART. VII. Experiments and Obfervations made with the View of improving the Art of compofing and applying calcareous Cements, and of preparing Quicklime: Theory of thefe Arts; and Specification of the Authors cheap and durable Cement for building Se By Bry. Higgins, M. D. 8vo. 5 s. unbound. Cadell, 1780.

TH

HE Author of this performance availing himself of the lights thrown on the nature of lime-ftone and calcareous earths, and their change into quicklime in the process of calcination, by Dr. Black, and thofe who have fucceeded him in this inquiry, was led to apply thefe discoveries to the useful purpofe of improving the mortar used in our buildings; on the goodness of which their ftrength and durability chiefly depend:

a matter, as he obferves, of great importance, in this country particularly; where the weather is fo variable and trying, and the mortar commonly ufed is fo bad, that the timbers of houfes laft longer than the wails; unless the mouldering cement be frequently replaced by pointing.'

Seeing however, the Author adds, that many years are requifite for the greateft degree of induration, which cementitious mixtures like mortar can acquire, or for our difcovering the imperfections of them; and that the life of man is too fhort to allow any confiderable improvements of them to be derived from fuch experiments as had hitherto been made; I refolved in the beginning of the year 1775 to investigate more clofely than I had hitherto done, the principles on which the induration and ftrength of calcareous cements depend; not doubting that this would lead me by an untried path to recover or to excel the

Roman

Roman cement, which in aqueducts and the most expofed structures has withstood every trial of fifteen hundred or two thousand years.'

Dr. Higgins accordingly first made feveral experiments, with a view to ascertain the changes which lime-ftones or calcareous earths undergo in the feveral ftages of calcination; particularly with refpect to the effential part of that procefs-the expulfion of the fixed air combined with them; the prefence or absence of which conftitutes the principal difference between lime-stone or chalk and quick-lime.

Among many other obfervations deduced from thefe experiments, we learn that lime-stone or chalk expofed only to a red heat, how long foever continued, ftill retains fo large a portion of its fixed air, (or acidulous gas,' as the Author denominates it) as to effervefce ftrongly with acids; and to lofe no more than one-fourth of its original weight; and that, in this state, it flakes flowly and partially, and with little heat:-and that exposed to a heat barely fufficient to melt copper, it lofes about one-third of its weight in twelve hours, and very little more in any longer time; that this lime effervefces but flightly in acids, heats much fooner and more ftrongly than the foregoing, when water is fprinkled on it, and flakes more equably, and to a whiter powder. In a variety of trials, this lime appeared to be in the fame ftate with the beft pieces of lime, prepared in the common Jime-kilns.'

From fucceeding experiments we learn further, that a white heat, fufficient to melt fteel, preceded by a long continued red heat, is requifite to expel all the fixed air from pure lime-ftone and calcareous earths; fo as to render them perfectly non-effervefcent, and to give them the properties of flaking instantly on the addition of water, growing hiling hot, and falling into a fine white powder. In the procefs thus conducted, 48 ounces of lime-ftone, after the total expulfion of its fixed air, lofes 21 ounces of its weight.

The Author next fhews, that the perfection of lime, prepared for the purpofe of making mortar, confifts chiefly in its being totally deprived of its fixed air. He afcertained the truth of this propofition, by making feveral parcels of mortar with lime which had been more or lefs ftrongly calcined; and had accordingly retained a lefs or greater quantity of its fixed air. He fpread each fpecimen, as foon as it was made, to the thicknefs of half an inch, on a plain tile previously foaked in water; and expofed them equally in an open place to the influence of the fun and rain. Comparing them at the end of fourteen or

For reafons that we have formerly affigned, we chufe to retain the old term, till cuftom has given a complete fanétion to a better. fifteen

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