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account which was then given of them in their united Aate, is applicable to the piece now separately printed; viz. that it is pious, rational, and practical. Such discourses cannot fail of doing honour to the Protestant Disfenters. It may be proper to add, that this second edition of the Charge is owing to the earnest solicitation of Sir Harry Trelawney. Some small parts of the discourse, which, for want of time, were surpressed in its first delivery, are here inferted.
CORRESPONDENCE. T has ever been our custom to pay due regard to the decent re
monftrances of respectable writers, who think their works, in any degree, misrepresented in our Review. On this principle, we publith the following letter from Mr. Hey, of Leeds, relative to our late account of his Observations on the Blood: see Review for November iall, Art. VII. Our strictures on that performance appeared, so us, to be just, at the time when we printed them ; and we do not apprehend that he will attribute them to any personal disrespect. To enter into a controversy on the subject, is not only unsuitable to the nature of our plan, but incompatible with our other engagements. What we have already said, is submitted to the judgment of oor Readers; and to the same respectable court we now coavey the plea of Mr. Hey, in his own behalf.
To the MONTHLY REVIEWERS. GENTLEMEN, Considering the great variety of subjects which come daily ender your notice, it cannot be deemed a want of candour to suppose, that sometimes the meaning of an author may be so far miltaken, as to occafion a criticism, which, upon second thoughts, you would wish to alter or retract. My partiality, perhaps, may lead me to think, that this remark is applicable to some parts of your criticism on my Obfervations on the Blood. I shall beg leave to poini out a few passages in which, I apprehend, you have mistaken my meaning, as well as that of Mr. Hewson, whose cheory of fizy blood I have animadverted upon.
The first passage I shall take notice of is that, in which you represent me as allowing the fundamental principle of Mr. Hewion's theory, and mistaking the meaning of his terms: “ This” (Mr. Hewson's) “ doctrine is, that inflammation, instead of increasing, lefens the disposition of blood to coagulate, and instead of thickening, thins it, at least its coagulable part. And Mr. Hey, instead of controverting this fundamental principle, admits as a fact, that the surface of blood which is about to form a crust of fize, remains much longer fluid, than that of blood in different circumstances. So far, then, they agree; but Mr. Hewson supposes, that what floats on the rura face of such blood is coagulable lymph, attenuated by the increased action of the blood vessels : whereas Mr. Hey contends, that it is coagulable lymph diluted with serum. We mult own, that the fer of experiments which Mr. Hey produces here, to prove (what nobody would doubt) that the tizy crust of blood really contains a watery or serous part, does not seem to us at all conclusive against the opinion of Mr. Hewson, who, by using the term attenuated, certainly 3
meant On the contrary, Mr. Hewson declares his opinion to be, that the more atlt. Fuated the coagulable lymph is, the less dilute is its consistence after coagulation. " The size is fonse:imes very firm, and at other times spongy and cellular; these differences in its denfity are, I suspect, in proportion to the degree of attenuation and left ned difpohtion of the blood to coagulate; for-be more ibe lymph is attenua:ed, and the flower it coagolare, the more will the film be able to separate it from the red globules and the serum i thence perhaps it is, that we sometimes see the whole coagulable lymph collected at the top, forming a firm cruft, &c. But when the bloor has its disposition to coagulate less diminished-then-the lymph-contajas a conliderable quantity of serum, and is of courie more spongy aud ulular." P. 105, 106.
meant to convey the idea of its being of a dilute or aqueous confitence. The cause here may be different ; but the effect, as far as discoverable by experiment, will certainly be the fame; dilution and attenuation being qualities not distinguishable, as we imagine, by common sensible ielts.” Monthly Review, November, p. 341.
From several parts of Mr. Hewson's Experimental Inquiry it apa pears, that by the term coagulable lymph, Mr. Hewson meant, that part of the blood which gives folidity to the crassamentum, and retains a folid form when separated from the serum and red globules. As p.6. "The crassamentum confilts of two parts, of which one gives it folidity, and is termed the coagulable lymph; and of another, which gives the red colour to the blood, and is called the red globales. Thefe two parts can be separated by washing the crassamentum in water, the red particles diffolving in the water, whilst the coagulable lymph remains felid." And again, p. 106. “ We sometimes fee almost the whole coagulable lymph collected at the top, forming a firm cruft, which being free from the ferum, as well as from the globules, contracts the furface into a hollow form:” though sometimes “ there is not time for its being separated from the serum, of which it therefore contains a considerable quantity, and is of course more spongy and cellular.”- In this last sentence, the coagulable lymph is as clearly distinguished from the feram which it contains in forming the wbite crust; as in the former it is distinguished from the red globules, with which it unites to form the crassamentum. I have followed Mr. Hewson in using the term in this strict and proper fense, though both of us have sometimes used it in a more lax way, for the white cruit itself found upon the cratramentum.
By the term attenuation, Ms. Hewfon meant to express the approach of a substance towards the Itate of perfect Auidity by an alteracion made in the fubfance itself; by dilution, the approach towards perfect fluiditv, by the addition of some other subtance of greater tenuity. When Mr. Hewson asserts, that the coagulable lymph is attenuated by inflammation, he does not mean to say, that inflammation causes the lymph to be of a more dilute or a queous confistence than usual, by the addition of serum, or any other fuid of greater tenuity than itself* ; for he expresly says, that “ the whole mass of blood seems to be thinner than the serum alone; or, that the coagulable lymph seems to be so much attenuared in these cases, as even to dilute the serum.” P. 55. But his meaning plainly is,
It is certain likewise, that Mr. Hewson did not think that the coagulable lymph was rendered thin, in its Auid fare, by the admixture of serum ; because he expressly says, that the coagulable lymph, when attenuated, diluted the serum. P. 55.
that inflammation increases the tenuity of the lymph, while circu. lating in the vessels, by altering its properties, and that this cenuity semains for some time after the blood is let out of the vessels, previously to its coagulation.
The force of Mr. Hewson's arguments, which are drawn from the properties of the fluid observed upon the surface of blood, when a white crust is about to be formed, depends entirely upon the supposition, that this fluid is coagulable lymph. My experiments have, therefore, in the plainest manner shewn these arguments to be inconclusive, by Thewing that the fluid is not coagulable lymph ; but that sometimes io, and sometimes pear fi of ic are something else, viz. ferum. Indeed, it is needless to attend to any arguments, which are designed to prove that this fuid is thinner than serum, as Mr. Hewson asserts; since the teliimony of the senses will soon convince any one of the contrary, who will give himself the trouble of examining it.
Your next paragraph relates to an inconsistency into which you suppose I have fallen by asserting, that the blood may, at the same time, have an increased proportion of coagulable lymph and serum. “ How these two opposite principles in the blood (one giving it density, and the other tenuity) can both be augmented at the same time, and from the same caule, we own ourselves at a loss to conceive.” Review, p. 342.
I have no where said, that the coagulable lymph and serum are increased by the fame caufe ; on the contrary, I have expressly attributed their increase to different causes, as in the following passages : • That the proportion of coagulable lymph is increased by inflammation, will be allowed by all,' &c. Obs. on the blood, p. 22. need not wonder, that the watery liquors, which are drunk pleati-fully in these disorders, should thin the blood.' Ib. p. 28.
Neither have I said that it (viz. the same thing) is at the same time thicker and thinner. But I have said, that the proportion of coagulable lymph and serum are sometimes increased ai che same time ; and I cannot see the dificulty, either of conceiving the por. fibility, or allowing the reality of this fact. Whenever we see the crallamentum of a very firm texture, or covered with a strong buffy coat, and throwing off a great quantity of serum, (which is the cale in violent infiammatory disorders after repeated bleeding) then we see the proportion of lymph and serum increased at the same time. And whenever this happens, the whole mass of blood will look thin as it flows from the vein; though the crafiamentum, by having more than its usual proportion of coagulable lymph, will be of an increased tenacity.
The last part of your criticism, which I Mall beg leave to take notice of, would have been obviated by comparing Mr. Hewson's expreffiors with mine, in our different accounts of the experiment made on the blood of laughtered theep. You would not, I think, have imagined, that our difference might arise in part, from the am. biguous use of a term. “ One cause of fallacy, indeed, we discern, in the different idea annexed to the term coagulation. Mr. Hey ob. serves, that the last blood was more viscid as it fowed, though it was the longelt in coagulating completely. Now viscidity differs only in
degree from coagulation, and therefore this might appear to Mr.
My account runs thus,
“ That blood which flowed ed when the animal became very last appeared the most viscid; or, weak, was quite fluid as it came 1 -Sufferid a partial coagulation as from the vessels. Exp. In. 70. it Aowed. Obs. p. 28. 2. “ Yet had hardly been re.
Yet was the latest in coceived into the cup before it con- agulating completely, and had the gealed-And-coagulated in an in- loftelt crassamentum.” Ib. Jant after it once began.” Ib. 71.
So that, whatever was the cause, “ the results” of our experiment, as you observe, were directly contrary to each other.
The design of my little essay has led me to take notice of the opinions of several authors whom I respect ; but I have aimed at doing this with such candour as I wish to experience from others. From fome excellent writings, and a short personal acquaintance, I judged Mr. Hewson to be a person of great ingenuity and industry : and I fincerely join with you in thinking, that experimental philosophy fuitained a great loss by his deacb.
Before I conclude this letter, permit me to offer one query for your consideration, Whether it does not tend to cast obscurity on the theory of sizy blood, to speak of a change in the nature of the coagulable lymph, as a thing diftinct from a change in its quantity ? For if the proper definition of coagulable lymph be, that which gives tenacity to ihe craffamentum, and retains a solid form, when separated from i be other constituent parts of the blood; it plainly follows, that when there is no tenacity in the crassamentum, nor any thing in the blood that retains a solid form after the separation of the serom and red globules, there is then no coagulable lymph. It is farely very unphilosophical to say, that the coagulable lymph, in such a case, remains undiminished, but has changed its properties ; for the idea we have of this fubitance is, that of something exhibiting these properties. I am, Gentlemen, your obedient humble servant, Leeds, Jan. 27, 1780.
William Hey. ... The receipt of a letter figned Juftus is acknowledged ; the Writer has our thanks for his hints; but we have no thoughts, ac present, of printing a General Index to our monthly collections : fee the last page of our Review for February. If any gentleman, or bookseller, chuses to risk a publication of that kind, we shall be far from opposing the design; and any allistance that we can lend toward carrying it into execution, may be depended on,-provided the plan be such as we can approve.
+++ A. Z. recommends to our notice a publication entitled, Tbe Reftitution of all Things, by J. White. As we have not seen this piece advertised, we are at a loss where to enquire for a copy of it.
For A PRIL, 1780.
ART. I. Conclufion of our Review of the new Edition of Shakspeare,
by Steevens, &c. See Review for January. E now fit down to fulfil our engagement to the Public
by presenting them with such extracts from the annotacions on Shakspeare, as, we presume, cannot fail of proving satisfactory to the admirers of that illustrious Bard.
In the first Scene, Act II. of the Tempest, Prospero says to Ferdinand,
for I “ Have given you a third of my own life.” Mr. Theobald was disfatisfied with the reading, and altered the text, by substituting thread for third. Dr. Johnson restored the old reading, and apprehends that Prospero, by calling his daughter Miranda “ a third of his own life,” alludes to some logical distinction of causes, making her the final cause. • Though this conjecture (says Mr. Hawkins) be very ingenious, I cannot think the poet had any such idea in his mind, The word thread was formerly spelt third, as appears from the following paffage in the comedy of Mucidorus (1619):
“ Long mailt thou live, and when the filters Thall decree “ To cut in twain the twisted third of life
" Then let him die,” &c. Mr. Tollet adopts Mr. Theobald's emendation, and observes, that Prospero confiders himself as the rock or parent-tree, and his daughter as a fibre or portion of himself, and for whose benefit he himself lives. In this sense the word is used in Markham's English Husbandman (1635) “ Every branch and third of the root," &c. Mr. Steevens confirms Mr. Hawkins's observation concerning the ancient method of spelling the word thread, by a curious quotation from an old poem, entitled, Line gua, published in 1607 : VOL, LXII,