THE Preſent Uncertainty IN THE Knowledge of Med'cines.

BEfore I come to Prove the Charge of Uncertainty on our Knowledge of Med'cines, 'twill be Neceſſary to lay down ſome Rules that may be Uſe⯑ful in examining the Matter of Fact. And theſe ſhall be taken from the De⯑ſcriptions of the Two different Sorts of Knowledge a Phyſician is ſaid to have; viz. Experimental and Scientifical; or, a Knowledge of Experience and Science. By knowing the Virtues or Powers of Med'cines in the Firſt Way, we know that ſuch and ſuch Med'cines are Recom⯑mended [2]for, and are good or bad in, Par⯑ticular Diſeaſes, and different Circum⯑ſtances of the Diſtemper, when either they have good Succeſs, no Succeſs, or an ill One. This is the loweſt piece of Knowledge that can be expected from Phyſicians.

Or, Secondly, If by many ſuch Experi⯑ments we ſhould diſcover what Action it is in any Med'cine, whereby it pro⯑duces its Proper Effects, ſo as to be able to deduce the good or bad Effects it will have, as ſo many Corollaries from the Knowledge of the Action, That wou'd be as Noble a piece of Science as Phyſick can be ſuppoſed to admit of, and wou'd con⯑tain all that is Neceſſary.

Having premiſed the Deſcriptions, which are the Rules in the enſuing Trial, I ſhall begin with all the Diſtinctneſs and Brevity imaginable.

But ſince the Bounds of a Letter will not allow me to try every ſingle Med'cine by it ſelf, or indeed every Claſs of Med'⯑cines in general; yet 'twill be more to your Satisfaction if I Prove it by Two or Three Examples of Med'cines, that are [3]either moſt in Uſe, or that produce moſt conſtantly the ſame Effects, when the leaſt Caution is had about 'em, and are in every one's Hands; and if I can Prove our Knowledge of them to be juſt nothing, and that it does not ſo much as arrive at the Firſt Deſcription or Experience, I may Preſume to conclude the like Imper⯑fection to be, at leaſt as great, in our Know⯑ledge of Med'cines, that are not near ſo frequently uſed, nor that have not, by far, ſo certain and conſtant Effects; nay, whoſe Effects are moſt unconſtant in the beſt Hands.

The Firſt Inſtance of this Imperfection ſhall be of the Jeſuits Pouder; a Med'cine that every one muſt own to be the beſt for Curing intermitting Feavers; and with that Certainty, that no other known Med'cine can do the like in this or any other Diſeaſe; for it generally Cures, not only in the Hands of Phyſicians, but e'en in thoſe of Quacks, and Nurſes, by whom it is given with no manner of Judgment or Diſcretion.

Yet even this Pouder has been wanting in its Succeſs, and Agues have been known [4]ſometimes to ſtand their Ground againſt many Charges of it. This is evident ſome⯑times here; but too often in Virginie.

'Tis known that by the taking of it, ſafe intermitting Feavers have been changed into thoſe that are continual; which are far more dangerous, and whoſe Event is often very doubtful.

And it is very ſurpriſing that this Turn of the Diſeaſe is not always in the ſame manner; for by Jeſuits Pouder Agues have degenerated into unweildy Rheuma⯑tiſms, or a lazy Jaundice; nay, ſometimes it has terminated in a ſudden Death.

Theſe are ſtrange and unconſtant Ef⯑fects of Jeſuits Pouder. It Cures an Ague the beſt of any thing; it turns the Patient ſometimes out of one Diſeaſe into another; and ſometimes it kills him.

But this is not all; it will ſometimes make him Coſtive; it Purges him; it Sweats him; yet it never has been ranked among Med'cines of theſe Sorts, but once to Diſparage it.

And this is the Rare Med'cine which Cures us ſo ſuddenly, that it ſeems to O⯑perate almoſt like a Charm, that yet has ſuch ſtrange, tho' ſeldom, ill Effects in the [5]Cure of the ſame Diſeaſe. But ſince dif⯑ferent Conditions and Circumſtances make all the Variety in this Affair, as well as in every thing elſe, Phyſicians ought to be very Induſtrious to find out what are the Conditions in this Caſe, where we find ſuch conſiderable Turns in Admini⯑ſtring this Excellent Med'cine. For, per⯑haps if they were known, they might be avoided; at leaſt, if a Cure is to be had by any other Med'cine, that rather is to be tried; and it is at worſt better not to attempt a Cure, than certainly to Kill.

'Tis to be thought, that if all, or any, of theſe ill Accidents that happen by uſing the Bark had often been obſerv'd, that no Rhetorick cou'd induce the World to perſiſt in taking it; yet ſince they have happen'd, they may happen again, and indeed every Day; it may therefore be thought very Expedient to know how ei⯑ther to give it ſo as to avoid Danger and Miſchief, or elſe to know when the Proper Time is when we are not to give it at all.

It was for want of this Knowledge the Bark loſt its good Name, when Sir—Ʋnder⯑wood, [6]Mayor of London, died by taking of it, whoſe untimely Death did ſo terrifie his Relations, that no friezing or fryings of an Ague can ever be ſtrong enough to force them to take it.

Now ſince there is ſo manifeſt Uncer⯑tainty in the Practice of this Excellent Med'cine; beſides the Danger of being killed; it muſt be own'd that there ought to be a good deal of Diſcretion had when we uſe it. And he who is poſſeſt of this Diſcretionary Knowledge, muſt be able to know, not only that it is un⯑certain, but this muſt be warranted by my Firſt Rule: He is obliged to know what Appearances, what Conditions, there were in the Diſeaſe; when the Bark Cu⯑red, and when it did not Cure; as alſo when One got a Jaundice by it, and a Third died. But if he has no Knowledge of thoſe Times, he is under a vaſt Uncer⯑tainty in every Patient; neither does he know whoſe Cure or Death he is carrying on with the greateſt Aſſurance, tho' he Practice with the beſt Med'cine.

I wou'd adviſe thoſe who think they can Anſwer for this Sort of Knowledge, [7]to try their Strength by the Second Rule I propoſed; but it is Time enough to do that when I find my Firſt Requeſt an⯑ſwer'd. Indeed by this Rule we have the moſt delightful, as well as the moſt uſe⯑ful, piece of Knowledge imaginable; for by it we might know what the Uni⯑form Action of the Bark is in it ſelf, whereby it Cures an Ague, and we ſhou'd be able to deduce theſe Miſchiefs that are already obſerv'd, as ſo many Corol⯑laries from the Condition of the Diſeaſe; nay, by it are we made capable to ſuſpect all the probable Dangers that can be, or perhaps have been, tho' they have eſcap'd the Caution of the Obſerver.

Theſe related Misfortunes that have happen'd by taking the Bark, are not the Calumnies it ſtands charged with by its bigotted Enemies. There are many more; but theſe I have named have happened to many Candid Practitioners, and the moſt of 'em Recorded by that Excellent Phyſician Dr. Sydenham.

But what can be ſaid to the Pother had among many Authors about its under Actions of Purging, Sweating, &c. when [8]they have Induſtriouſly paſt by ſo Con⯑ſiderable Effects of this Med'cine.

All the Uſe I make of this Argument for the Preſent, is to ſhew you that the Knowledge of Med'cines is as Obſcure and Difficult as any thing elſe in Phy⯑ſick, notwithſtanding of a common O⯑pinion we entertain about their Certain⯑ty. And this I think is very manifeſt by this Firſt Inſtance; becauſe our Know⯑ledge of the beſt Med'cine which anſwers Expectation moſt conſtantly, and is more us'd than any one Med'cine, is very ob⯑ſcure, and juſt nothing at all.

This Argument might be purſued as Succeſsfully in every one of the Med'cines that are moſt Familiar to us. In all Eva⯑cuating Med'cines, as well as in thoſe that produce no Evacuation, but are conſide⯑rable for ſome great Effect of another kind; but ſo Particular an Aggravation is by no means Neceſſary, neither does the preſent Occaſion require it. I ſhall content my ſelf with an Inſtance or Two more, which will be ſufficient to Prove my Argument about the real Uncertain⯑ty of Med'cines.

The next Example that I bring is of Opium; and I cannot help thinking it thus Uncertain, notwithſtanding of the late Endeavours of ſome Ingenious Au⯑thors, being there is not full Satisfaction given about its way of producing Sleep; and far more hardly are we preſt when we endeavour to account for its Action when it hinders us from Sleep, and makes us Delirous.

Moreover, Opium is obſerv'd to give a Check to all Sorts of Evacuations; yet great Evacuations have been known to be made by it.

'Tis noted for either relieving us of Pain, or at leaſt giving an agreeable reſpite from it, though great and torturing Pains have ſometimes been felt upon its Account: I mean not only thoſe Head⯑achs, and Pain at Stomach, it often occa⯑ſions, and that are felt after its ſleeping force is over; but even ſome that come at firſt taking, and that beyond all Pa⯑tience, and almoſt to Diſtraction; yea, theſe Pains are alſo produced by every thing that makes Sleep, as well as by Opium, or any Preparation of it; and [10]the more Obſtinately we perſiſt in that quieting Deſign, to greater Degrees we augment the Torture.

Beſides all this, Opium is not like other Med'cines ſo eaſily dos'd; and an exceeding quantity has worſe Conſequences than any other Med'cine whatever. Nay, ſome⯑times when we wou'd give it to good Purpoſe, it is Neceſſary to give Three or Four Grains at once, withour our coming Cautiouſly, and by Degrees, to that Quan⯑tity; or that it is given to People who have been long accuſtomed to take it, (all which Conſiderations alter the Caſe per⯑fectly), yet there is nothing more Certain, than that Three Grains have laid People of a proper Age into an Eternal Oblivi⯑on of this World; tho' the World ſhould not forget him that gave it.

Now who wou'd not Purchaſe at any Rate a good Night's Reſt, after watching many Nights, and a long Vigilia? Who wou'd not rid themſelves of Trouble⯑ſome Pains, and uneaſie Evacuations, by taking Opium? But if the Danger that poſſibly may come by it was ever imagin'd, how equal might the Diſpute prove a⯑bout [11]taking of it on any of the men⯑tioned Deſigns; but eſpecially if the Ope⯑ration of this Med'cine ſhou'd fall ſhort of it; nay, if the contrary Effects were ever ſuppos'd to happen. We ought to ſuppoſe at leaſt that a very Extraordinary Pilot ought to be made Choice of, to guide us where ſuch Hazards, and Things of ſo great a Value, are; and more where our Perſons may be fatally concern'd.

And therefore let any One who pre⯑tends to be familiarly acquainted with this Pacifick Med'cine, examine himſelf throughly by the Rules I have laid down, and reſt ſatisfied with nothing leſs than his being qualified by the Firſt.

I confeſs it is ſtrange enough to hear Men Boaſt of a Certainty in Med'cines, ſuch as requires no Direction from Reaſon to Manage beyond their Skill; and yet ſuch conſiderable Doubts to remain at this Day about a Med'cine of ſo manifeſt Ef⯑fects, and of ſo great and ancient a ſtand⯑ing. Wherefore it is manifeſt how pro⯑per an Example this is to Prove our Im⯑perfection about the Knowledge of Med'⯑cines.

But no leſs an Imperfection may per⯑haps be found in another Ancient Method of Curing, which commonly is the ut⯑moſt Skill, and laſt Reſort of a Doctor, after other Experience and Med'cines have been practis'd to no Purpoſe. And after ſo Honourable a Mention made of a Me⯑thod, every Body muſt think it is only Proper to the Bath, as indeed I intend it. I muſt not be thought to Depretiate either the bathing or drinking of Waters at Bath, which I do by no Means. On the contra⯑ry, I have a valuable and juſt Eſteem of 'em.

Only I do ſay, that this uſeful and an⯑cient Method is far from being ſo ſuffici⯑ently known, that we are able to reap all the Benefit of it, or to avoid all its Miſ⯑chiefs, as ſhall be made appear immediate⯑ly by Particulars.

As to its Antiquity, 'tis believed that People applied themſelves to it for Relief in their Maladies before the Romans were much known in Britain; yet if we com⯑pare what has been ſaid of 'em, either as to their Warmth or Medicinal Effects, by Ancient or Modern Writers, we ſhall [13]find how little theſe have improv'd what the former aſſerted. Cambden informs us how Old Necham has conceived the Obſer⯑vations of his Time about theſe Waters, for their Uſe.

Then he, and moſt Moderns after him, aſſign this Reaſon for the Heat of theſe Waters.

At preſent I am not bound to make all Proper Inquiries about the Bath; but in ge⯑neral, I will firſt obſerve how diſproporti⯑onable the Fame of the Cures it has work'd are to its long ſtanding, and great Character given it by ſome Men. And, 2dly, The extream Changes its Reputation has ſuf⯑fer'd in that Tract of Time: 'Thas often been eſteem'd a Panacea, and too frequent⯑ly thought good for nothing at all. And from both theſe Obſervations I conclude, [14]that if a moderate Knowledge of this Method had been join'd with half the good Uſes of theſe Waters, they never cou'd have had ſo great Ebbings in their Fame.

But to be more Particular; 'tis certain, that though Sulphur impregnating thoſe Waters, is told us to be the Cauſe of their Heat; yet our Knowledge of this Method of Nature is ſo very obſcure, that we can neither imitate her in medicating Wa⯑ters after that manner; nor by any Means make other Waters Serviceable to like Purpoſes. Wherefore it is alſo mani⯑feſt how Inſignificant our boaſted Know⯑ledge is, and to how little Purpoſe our Trials of 'em have been.

I know that there are Authors that Prove, and ſufficiently enough, that thoſe Waters contain more Subſtances than Sul⯑phur; but the Difficulty remains the ſame, mutatis mutandis, viz. by taking the known Compoſitum, as I took Sulphur ſingly in the Argument.

But further, if I ſhould ſuppoſe that either the ſingle Ingredient of theſe Wa⯑ters, if there is but one, or a determin'd [15]Quantity of Ingredients, if more were known; yet it is certain we ſhould be ſtill Ignorant of their Operations, if we know not the Effects of theſe ſimple Sub⯑ſtances, which being mixed with the Wa⯑ters, give 'em their Medicinal Qualities; and the Difficulty wou'd always encreaſe, when we were to account for their Combi⯑nation. This is manifeſt from the Affair of Jeſuits Pouder, i.e. it is manifeſt that if the Particular Ingredients of theſe Waters were in Subſtance and Quantity as evident to us as the Subſtance and Quantity of Je⯑ſuits Pouder, yet our Difficulties ſhall ſtill remain unſatisfied, except we knew more of the Nature of theſe Subſtances, that are the Compoſita of the Waters, than we know of Jeſuits Pouder; and I think we know leſs, and by Conſequence leſs alſo of the Waters, even ſuppoſing we knew their Compoſition.

But let us ſuppoſe that the Bath is good for decay'd Old Age; for People that are Lame, and thoſe who labour under a Diſ⯑eaſe from a Cold Cauſe; yet our Know⯑ledge about the Bath muſt remain Uncer⯑tain, if we are not able to juſtifie our ſending People thither on other Accounts, [16]for Reaſons not yet aſſign'd; and if we cannot ſhow that Effects quite con⯑trary to thoſe it is noted for have not hap⯑pen'd, with the Particular Circumſtances of the Caſe.

Inſtances of the laſt Sort are adduced in a good Number by Bath Doctors; and though poſſibly the Crutches that hang there may not be the Martyrology of the Bath, as Doctor Willis wou'd have it; yet they are confeſs'd not to be the Tro⯑phies of its conſtant Succeſs. But it is moſt certain that we have not conveyed to us the Failings and croſs Succeſſes which are abſolutely Neceſſary for the ſmalleſt Degree of Certainty in this Affair.

Perhaps the ſending People for all Diſ⯑eaſes may be alledg'd for its great Uſe: And I do Concur with them who ſay ſo, though I think very meanly of the Judg⯑ment of the Phyſicians who do ſo; and am Poſitive, that how ſoever excellent the Bath may be, that it neither is Infallible, nor a Panacea; but that it will always want a ſuitable Direction, which will be the more Infallible the greater our Knowledge is.

But the Weakneſs of our Underſtand⯑ings in this Particular is but too mani⯑feſt by ſome Facts I ſhall Adduce.

For we know that many People who have been forſaken in the Jaundice by their Phyſicians, have yet found their Health at Bath, though the Bath is accuſed for bringing the Jaundice upon a great many.

It has been the common Complaint, eſpecially for theſe Two or Three laſt Years, that a vaſt Number of People have got Rheumatiſms at Bath; it is notwith⯑ſtanding moſt inconteſtably True, that great Numbers have got rid of Rheuma⯑tiſms there.

Many more Examples of other Diſea⯑ſes might be brought to Prove this Thing, beſides the ſudden Deaths that have hap⯑pen'd there; and yet I am apt to believe that it is very hard to account for theſe Accidents, even by my Rule of Experi⯑ence, which but too ſufficiently Proves the great Imperfection our Knowledge lyes under in this very Matter, of the moſt ancient and uſeful Method of the Bath.

But I am aſham'd to think that this an⯑cient and uſeful manner of Bathing ſhou'd [18]begin to be ſo much neglected, as if it neither wanted, or did not deſerve our im⯑proving. No manner of Conſideration is had about making it have its beſt Uſe, which is ſo little known, that ſome great Phyſicians are ſcandalouſly Nice by giving the Waters by Spoonfuls: As if Old Ex⯑perience was to be laid aſide to make way for ſuch as they wou'd call New.

What Conſiderations are rais'd about Ba⯑thing? What Inquiries are made about our being Immerg'd in Water? What Queſtions are ask'd about its entering or not entering our Veſſels? And what Effects it may pro⯑duce by mixing with the Liquors in 'em? And, Laſtly, what may the Difference be in being Immerged in Hot and Cold Water?

Theſe Conſiderations are not only Fine, but Uſeful, and wou'd ſoon make us Ma⯑ſters of all that Affair. 'Tis ſure a Maſter⯑piece of Impudence to pretend to a Know⯑ledge very Particular of any Bath, and to remain Ignorant of theſe Particulars I have juſt mention'd; nothing can be more ſtrange, except the ſetting no Value upon ſuch Inquiries, as thoſe Pretenders are ve⯑ry ready to do.

But not to preſs this Argument any far⯑ther, I may be apt to think that there can be no manner of Doubt about the great Imperfection of our Knowledge in reſpect of Med'cines; and how Ineſtimable a good it wou'd be to be brought out of this In⯑firmity.

But, Gentlemen, to put an End to this Matter, I have not only given you Med'⯑cines of moſt ancient and common Uſe, but I have but juſt nam'd ſuch of their Ef⯑fects as are recorded by the beſt Authors; and which conſequently cannot probably be falſe. 'Tis therefore your Buſineſs to give Satisfaction to theſe Examples I have Adduc'd, and that by your Quality-Method of Hot and Cold, Red and Yellow, Acid and Alkaly, by Taſte and Smell, &c. or becauſe you love high Flights by the Cauſes of theſe Qualities; yet if you have any Regard to my condeſcending to give you a lower Method, I Challenge you to give ſuch Proofs in Point of Experience that may aſſiſt our adminiſtring them in Practice.

But while I ſpeak to your Method of Qualities, I muſt inform you how Igno⯑rant your Pretence is in this Particular. [20]You pretend to determine the Power any Med'cine has to Cure a Diſeaſe only by knowing ſome of Its Notable Qualities, which is manifeſtly falſe; becauſe there is ſcarcely one Diſeaſe that has not Med'⯑cines of oppoſite Qualities found uſeful in its Cure, and recommended to us by our Forefathers as ſuch.

This is a Digreſſion, but not an impro⯑per one; yet to proceed; is the previous Knowledge of a Med [...]cine, or of Med'cines, by its or their Qualities, neceſſary before we Adminiſter them? And have you this kind of Knowledge? If you have, ſhow it us, for it is much wanting. If you have not, then require no more of others than you your ſelves are Maſters of; and order as few Med'cines for the Publick as you do to Patients; and none to either of 'em till you have ſatisfied us that you can do it in the mentioned Way.

But if you have any tolerating Method whereby you wou'd juſtifie your admini⯑ſtring Med'cines in your Probation Time, do as you wou'd be done by; ſhare your Freedom to others of your Brethren, who are at leaſt in no lower a form of know⯑ing than you be.

And if you have a ſpecial Rule where⯑by you can prefer the Uſe of one Med'cine to that of another, for the Cure of the ſame Diſeaſe: If you have, viz. any Me⯑thod for which you wou'd rather give Jeſuits Pouder for the Cure of an Ague, than any of the other Med'cines recom⯑mended for the ſame: Let us have this your Method of reaſoning; for it may be ſo extenſive as to comprehend more Med'⯑cines in this and other Diſtempers.

I know the Trite and Common Methods among Philoſophers, and all Mankind, is firſt to know if a thing is ſo, and then how it is ſo if we are able to compaſs it; but if they ſhould not get this length, you muſt reckon thoſe little better than Mad-men that deny the actual Exiſtence of a Thing, becauſe we do not know the Way of its Being. And but juſt⯑ly, becauſe it wou'd have us disbelieve our Senſes, and the Senſes of all Man⯑kind; becauſe we cannot anſwer ſome Queſtions that are, or that happen not, to be the Objects of our Senſes, and are too fine for our Underſtanding. So that in the Trial, if a Man, or a Thing, is, or [22]does, ſuch an Action, or produces ſuch an Effect, we muſt judge of theſe Changes by our Eyes and other Senſes, or take them upon the Teſtimony of Honeſt Capable People that relate them, if we were not there our ſelves. This is the Way of the World, and I ſhall not enlarge upon it, to avoid Scandal: Tho' ſo much I muſt ſay, becauſe you and your Friend have ſo boldly unhing'd all theſe common Ways of judging of paſt Actions, that I am not able to go further with you, till you have inform'd us more in thoſe new Me⯑thods; yet whether you will do it or not, depend upon it, a Time may come where⯑in the World ſhall be informed how you uſe their old ones in Matters of the great⯑eſt Importance.

Thus I bid you Farewel, knowing to how little Purpoſe it wou'd be to invite you to the following Diſcourſe. For you never once dreamt of any ſuch thing; and your proper Talent is to Snarl in a Corner at ſo Generous Attempts.