as it has been odiously infinuated, in order to prejudice thofe against him, who retain a tender Efteem for the Memory of Boerhaave. Nei:ther is it my Defign to beftow Encomiums on Boerhaave's Commentator, but leave this to the Royal Academy of Sciences in Paris (a), the · Royal Society in London (b), and M. Winflow (c).

My fole Defign is to confound the Envy of a Libeller, who has put on the Mask of Zeal for Boerhaave, in order to calumniate the most · faithful, and, as I have heard, in one of the firft Courts in Germany, the most favorite Difciple of that great Mafter; has without the least Reason affronted the Perfon among Boerhaave's Difciples, who laboured most for his Glory, (d) and testified the highest Gratitude to him; who makes it his Business to criticise on a Discovery made by M. Haller, of which the Reader may take the following Account.

The Question in difpute is the Circulation of the Blood in the Foetus. Haller defends the Sentiment of his Mafter, which is that of Harvey and Duverney. Tho' Boerhaave had defended this Doctrine before Haller, yet he had left the fundamental Difficulty, which conftitutes the whole Force of M. Meray's Syftem, without any Answer. This Difficulty is, That in a Foetus, the pulmonary Artery is much larger than the Aorta.

Let us compute that there are 15 Parts of Blood coming to the Heart thro' the two Vena Cavas. Let us fuppofe, with Boerhaave, that a third, or any given Quantity of this Blood paffes thro' the Foramen Ovale, and enters the left Sinus, without paffing into the Heart, and confequently not into the pulmonary Artery. This Artery will only receive from the Heart 15-5, that is of Blood from the two Vena Cavas. Let it furnish, by the arterial Duct, the 5 other 15ths to the Aorta defcendens, or any other Quantity, but fuch as is equal to that of the Foramen Ovale. This Aorta will have in its Aperture, thro' which it receives the Blood from the left Ventricle of the Heart, five Parts of Blood convey'd thro' the Foramen Ovale, and five others which have remain'd in the pulmonary Artery, after the arterial Canal has carried off five. This makes 1, which is precifely the fame Quantity which the pulmonary Artery receives. Thefe Quantities ought therefore to be equal; but whence comes it that they are not fo?

I think I have read enough to affure myself that this Objection is not fufficiently anfwer'd, and believe it will be hard to produce a fingle Author who has fo much as thought of the Solution I am about to give.

The Foramen Ovale only receives a fifteenth Part of the Blood convey'd by the two Vena Cavas, because the Square of its Diameter in a Fatus of nine Months is but a 15th Part of the Areas of the Orifices of the two Vena Cavas. Into the right Ventricle therefore of the Heart, and into the pulmonary Artery, there pafs of the total Blood of the Vena Cavas 15-1 that is in all . The pulmonary Artery fends.

to

(a) See the Judgment given of M. Haller, by the Secretary of the Academy of Sciences, Hiftoire 1743.. (b) See the Extract of the Enumeratio Plantarum Helvetiarum of M. Haller, in the Philofophical Tranfactions, N. 468. (c) In the Memoires 1732. where Winslow gives an Extract of Haller's Treatife of Monsters, and in those of 1743. (d) Haller having publifhed feveral Works of that great Man, and being at prefent employ'd in writing his Life in quality of an Hiftorian,

to the Aorta defcendens the Half of its Blood at least, because the arterial Canal is at least equal to two Branches of the pulmonary Artery taken together: In confequence of this, the Aorta only receives from the left Ventricle the of what it conveyed to it, thro' the Foramen Ovale, with the remaining in the pulmonary Branches, after the arterial Canal has carried off the other of it. The Aorta then only receives 114 makings of the Blood of the Vena Cavas, whereas the pulmonary Artery receives of it, fo that this latter must be much larger than the former. This is, in my Opinion, an eafy Solution. As for the anatomical Facts which ferve as a Bafis for our Calculation, they are afcertain'd by many repeated Experiments; and tho' there should be fome Variations, yet 'tis ftill certain that the arterial Canal is much larger than the Foramen Ovale, which is fufficient to confute the most obatinate Wrangler.

The second Criticism relates to an anatomical Fact propos'd by M. Haller, This Surgeon thought, before his Antagonist, that this Fa&t was oppofite to the common Opinion. Of this he appris'd his Readers, told them what he had feen, and did not want them to prefer his Defcription to that of other Anatomifts (a). As the Question in difpute depended on no lefs than the Mifreprefentation of a Fact, the Critic ought to have applied to M. Haller. I fhall give the Reader the following Account from M. Haller's Works.

"On the 19th of September, 1739, there was brought to me a falfe Conception of a Lady, who receiv'd a Wound, when, according to her Account, fhe had been pregnant fix Weeks. I wafh'd this Egg with clear Water, and examining it with great Attention, found it entirely cover'd with a thick Membrane, which could be no other than the Chorion. Under this Membrane, when torn by the Midwife, I found the Placenta filamentous as ufual. Upon tracing it, I faw its Filaments detach themselves from the Amnios, in order to spread themselves in the Intervals of the Amnios and Chorion, which bounded its Filaments." "Another Egg, of a fimilar Structure, was brought me in April 1741, and fome others during the fubfequent Course of my Diffections, Thefe are the Facts on which is founded the Defcription which I have given Page 29. Part 2. of my Commentaries. Confider, Sir, if they are fufficient for my Defence. One of thefe Eggs is preferv'd among the Preparations of our Theatre."

Here then is an attefted Fact, which our Critic gives as an enormous Blunder in Anatomy. Occafions of confirming Facts of this Kind are very rare, which made M. Haller speak with a great deal of Reserve concerning his Obfervation, which however contains nothing but what is analogous to what we fee in Eggs farther advanced. Moft Anatomifts, and especially M. Nortwyck, agree with M. Ruyfch that these Eggs are entirely cover'd by the Chorion, that the Placenta lies under this Membrane, that the Amnios is interiour with refpect to the first, and that confequently the Structure of a human Egg of three Months is precifely the fame with that which M. Haller obferv'd in an Egg of fix Months.

The only Difference is the Growth of the Placenta, that furrounds

(a)Comment, Boerhaave, page 229.

the

the whole Egg in the Foetus, when very imperfect, which only poffeffes a Part of it, when it is more advanced. But in this Part the Structure remains fuch as M. Haller faw it in a younger Egg.

As an Example of the erroneous Hypothefis of M. Haller, our Critic advances two Conjectures. The firft afcribes umbilical Vefels to the Wormling. It is there faid that theie Venels appear to depofite fome fuperfluous Humours, and attract others in their fiead. According to the Syftem of Developements, follow'd by Boerhaave, this Conjecture most have been very plaufible, for according to this Syftem there have always been in the Foetus two large Branches of the Aorta, called umbilical. Thefe have always been convey'd to the Navel; whilft at the fame time the Foetus adher'd to Nothing, but like a kind of Eel floated in the feminal Liquor. Thefe open Arteries, therefore, probably threw into the feminal Liquor a Part of that which fupplied the Foetus. The Rea foning is the fame for the umbilical Vein: According to the fame Syftem, it always exifted in Man when a Worm; it went to the Navel; it correfponded to the Liquor in which this Infect, deftin'd to be reafonable, fwimm'd; why should it not, therefore, fuck it out? But it is vain to dwell upon a limited Conjecture, which ferves as a Foundation to nothing, which is neither a Syftem itself, nor deftin'd to fupport any, and which M. Haller has long ago abandon'd (a), having quitted the Syftem of Developements, after the Experiments on Polypufes.

As for the other Conjecture which offends the Critic, it is evidently true. All aquatic Infects, Polypufes, and ftill more minute Animals, have a Mouth, by which they fwallow either Water, or the Juices of Plants, or thofe of other Animals; why therefore should not Man, when a Worm, nourish himself in the fame Manner, and what other Mechanifm can be more natural for his Support?

(a) Comment. Boerhaave, V. p. 11. pag. 500.

TH

HAT every man ought to have liberty to worship the fupreme being in that way, or manner, which he thinks most just and eligible; that even the religion of the bleffed Jefus is not to be forced upon men by any methods of violence; and that the great author of Christianity accepts of none for his fervants, but thofe who, from a full conviction, have made his fervice their choice, are truths that have gained a general reception among Proteflants.

But then, that people ought not to oppofe, and labour to undermine the government they live under, and that every wife and well ordered ftate ought to take cognizance of, and feverely punith fuch offenders, is the voice of reafon, and the voice of God.

As every man gained over to popery is an enemy to the flate, becaufe he acknowledges the fupreme authority of the Pope, and under him that of the Pretender, it is very plain, that it must be the wisdom and intereft, as well as duty of the ftate, to oppofe, by all lawful means, the growth of popery: Not by laying a reftraint upon confcience, but

by

by ftrictly guarding against those evil arts that Papifts make use of to

Increase their numbers.

Among all the arts and machinations of Papifts to increase their party, that of their intermarriages with Proteftants does them moft service, by increafing their numbers; their craft now, like that of falfe prophets of yore, lies in leading captive filly women laden with divers lufts, and when they have obtained their end, they feldom fail to match the deluded (if not debauched) wretches to weak-headed Proteftants; ever laying a strict charge upon them before marriage, to agree with their intended conforts to have the children all brought up in their own way; by this means the whole family is fecured on their fide, and very often the husband himfelf is gained over as a profelyte: If there be not a fpeedy ftop put to it, they will very quickly prevail against us by dint of numbers; for in 20 years, they have increafed from 15 to 40, only in one Parish in the county of S.

Now, if our legiflators would but confider this matter, and enact that the penalty of tranfportation, or fome other heavy punishment, or fine fhould be inflicted on every Proteftant who marries with a Papift, fuch a law would foon put a stop to this growing evil; and not only fo, but our women would be fecured from feduction: Befides, it would have this further good effect Proteftants and Papifts would, in a little time, become perfect aliens one to another; so that there would be no refpect paid to the latter on account of confanguinity, but as their hand is against every man, fo would every man's hand be against them : And further, popish priests could not, as they do at prefent, by one friend introduce themselves into the company of another.

But perhaps it will be faid, the edge of this law will be cafily avoided by perfons guilty of fuch criminal combination; for it will be only declaring that they were papifts when they married, and the punishment will not reach them. To prevent this, I would have the law made, thar every perfon (man or woman) reputed a proteftant, and marrying a papist, or reputed papift, fhould be liable to the penalty; unless he or the have made oath before fome one of his majesty's justices of the peace, one year before fuch marriage is folemnized, or reputed to be folemnized, that they are really of the Romish communion: The weakeft Proteftant will be ashamed of doing this, and those that do will be known, which will be a very great advantage.

Such a law as this can't be thought any impofition upon the confcience, fince there'is no Proteftant who understands his own principles, but muft in confcience fcruple fuch an alliance; and if there be any fo ftupid as to prefer the popish religion to his own, the law does not hinder him, let him embrace it.

This, I think, would be the most effectual political means to prevent the growth of popery, and as fuch, I humbly recommend it to thofe honourable and loyal gentlemen, who have it in their power to propose it in a proper place.

I am, Sir, Your bumble fervant,

THEOPHILUS.