N TME CUSTODY Of TtiE

BOSTON PUBLIC LIBRARY.

SHELF N°

PHILOSOPHICAL JEMPIRICISMs

CONTAINING

Remarks on a Charge of Plagiarism refpefting Dr, H^- — s^

INTERSPERSED

With various Obfervatioms relating td DIFFERENT KINDS of AIR;

ByJOSEPH PRIESTLEY, LL.D. F.R.S.

Vivitur ex rapto. Non hofpes ab hofpite tutU3.

OviDi

LONDON:

Printed for J.Johnson, No. 72, St. Paul's Cburch-jardi^ 1775. (Price One Shilling and Six Pence.)

' ADAMS W.i

/f- J ■:;»

ADVERTISEMENT.

Though this piece was originally intended to anfwer a temporary purpofe, it is likewife calculated to refute fome prevailing miftakes concerning the dodrine of air^ and therefore will, I hope, be of ufe in eftablifhing funda- mental, and juft principles in this branch of Natural Philofophy, which is now become ant objed of very general attention.

I have not publifhed the name of my anta- gonift at length, partly becaufe I am really aftiamed of fuch a conteft ; and alfo becaufe I would not do him any more injury than I was obliged to do in my own juftification. It will not be expeded, I hope, that I Ihould be quite grave and ferious through the whole of this affair. I have been, I think, fuffi- ciently fo at the beginning ; but the occafion did not require it throughout : and, indeed, it was not in my power to treat this very abfurd and ridiculous accufation, but with a great mixture of ridicule and contempt.

Since the writing of this pamphlet, Mr. Godfrey (of whom Lmade fome inquiry con- cerning the converfion of earth into water, men- tioned p. ^j) has been fo obliging as to favour A 2 me

ADVERTISEMENT.

me with part of a quantity of earth that had been produced from diftilled water, weight for weight, by that celebrated chemift his grand- father^ the cotemporary of Mr. Boyle^ and his fellow-labourer.

This earth, I find, yields fixed air in great plenty, by the heat of a burning lens in quick- iilver, as well as by means of the acids". And when it is made into a pafte with fpirit of nitre, it yields more air, the greateft part of which is alfo fixed air. This experiment I barely announce at prefent, as exhibiting a hew fadt refpefling the generation of fixed air^ that can-^ not be publilhed too foon.

THE

/

THE

1 N t it O b U C T I O N,

C(>NTAIN1NG

TThe Letters that pr-.fled between the Author, Dr. H s^ and Dr. Brocklesby,

IT is witjli .much feludance, as feveral of my frjeqds can witnels, that, after with- ftandingi as long as J could, their earneli remonftrances on the fubjed, I have been in- duced to make this appeal to the public; 1 having been willing to think it unnecefTary, and they infifting upon it that it was abfolute- ly necefliiry. At length I yielded to their reafons. The cafe is as follows.

Before I left London, in the fpring of the prefen-t year, in which my acquaintance with

Dr.H s commenced and terminated, I was

told it was reported, that fome of my new ex- periments, of which I had fenc an account to B the

2 Philofoph'ical Empirlcifm.

the Royal Society, fubfequent to my acquaint- ■ ance with him, were only the reiult of his^^- neral principles concerning air; and Dr. Brock- lefby, when he faw fome of my new experi- ments, in the company mentioned in my letter to him, faid of them all^ without diftinftion,

that they were thofe that Dr. H s had

fhewn. But as I knew that Dr. H s and

myfelf held no common principles concerning air, as Dr. Brocklefby had not the character of being the moil accurate man in the world, and I thought that my charader for veracity^ at leafr, was fufficiently eftablifhed, I intirely neglefted the infmuation, and really thought no more about the matter, till I was informed, by a letter from London, while I was in the country, that the report of my having taken

feveral things from Dr. H s gained

ground.

Knowing, however, that there could be no foundation for this charge, I continued to pay no attention to it ; and though, upon coming to town, I found it was in every body's mouth, and my friends urged me to make fome in- quiry concerning ir, I neglefted to do it for a confiderable time-, thinking that the publi- cation of my fecond volume of Ohfervations con- cerning Air, which was then nearly printed off, would fpeak for icfelf, and fatisfy every body

who

Philofophical Empiricifm. ^

who fhoiild perufe it, thatvthe narrative carried its own evidence along with it.

But I was told that the charge of plagiarifm, abfurd as it was, had been fo long, and fo in- duftrioufly circulated, without having been contradidcd by any proper authority, that it had really gained much credit; that many per- fons, without diftinguifhing times or dates, had publicly, and with great confidence advanced, that even ail my difcoveries had been taken from the fame Dr. H — — s. On this account, not only my friends, but perfons with whom I had no ftrift conneflion^ affured me that, in their opi- nion, it really behoved me to make fome re- gular inquiry into the bufmefs. Accordingly I did, at length, though with great rekidlance (ftill hoping that there could be no neceffity for any appeal to the public upon the fubjed) fet myfelf about it -, when I prefently found what the following letters will fpecify.

To Dr. Brocklesby. Dear Sir,

The bufinefs I write to you about is fo irk- fome to me, that I have deferred it as long as polTible, hoping there might be no occafion to

B 2 eive

1^ -Phtlofophical Empricifin.

. give yaii any trouble on the fubjeft. At length, however, I have been perfuaded by my friends to do it.

It is reported, 1 find, that fome experi- -ments, which I have lately exhibited as my

own^ I took from Dr. H s, and where-

ever I inquire about it, I am told that you .charged me with it when you Auv my experi- ments at Shelburne-houfe, in company with Dr. Fothergill, the two Dr. Watfons and Dodqr and Mr. John Hunter*.

Now as you did not at that tiane charge me .with any p.Iagiarifm, but only fuppofcd that

both Dr. H- s and myfelf had made the

•fame -difco very, and did not even fay that you •had yourfelf feen thofe experiments of Dr. iH- — :fs's,. I muft beg the favour of you to tell nie \f{h'aX.i\iofQ common experiments 'wcvt^ and by what authority you took upon yourfelf to fay, that the experiments you then law were the

fame with thofe of Dr. H s's, which you

had not feen ; for, if I remember right, I fhew- ed you fever al at that time, which were not mentioned in my firft volume.

-I have not heard that Dr. H — - — s himfelf charges me with having taken any thing from

him;

* This was on the 23d of Ma/, 1775.

Philofophical Emphicifm.^ fj

him-, and with refpcft to ;the prtnclpal thing which 1 then ihevv/ed'you as new, it is impofli- ble tliat he fhould have claimed it> when, as I immediately told you, in the prefence of the' gentlemen abovementioned, it was but a little time before, that he had hefitated to admit the fads when 1 mentioned them to him j as, in- deed, I iLould liave done myfelf a little before that, had any other perfon mentioned them to me ; the difcovery of them haying been per- fedly accidental, and affording no foundation for merit whatever.

What he advances in his printed Syllabus is' the^ery reverfe of my ideas on that fubje^, and, in my opinion, is contradicted by the ex-' periments I then fhewed you. Indeed, it is'

now abundantly evident, that Dr. H s and

myfelf have hardly one common idea concern- ing air ; fo that if he be right, mod of my difcoveries are, what he has thought proper to call them, mere conceits \ and if i be right, his general dotlrine is entirely chimerical and falfe. On this account, it is hardly poflible that we fhould have taken any thing from each other ; except thai: he has adopted fome things con- tained in n\y firjl volume^ the fecond edition of which had been publifhed fome time before I had fo much as heard the name of Dr. H ^5.

B 3 In

4

Phllofophical Empricifin.

give you any trouMe an the fubjeft. At length, however, I have been perfuaded by my friends to do it.

. It is reported, 1 find, that fome experi-

• nients, which I have lately exhibited as my

owttj. I took from Dr. H s^ and where-

ever 1 inquire about it, I am told that you charged me with it when you Hiw my experi- ments at Shelburne-houle, in company with Dr. Fothergill, tht two Dr. Watfons and Dodor and Mr. John Hunter*.

Now as you did not at that time charge me .with any plagiarifm, but only fuppofcd that

both Dr. H-^ s and mylelf had made the

•fame .difcovery, and did not even fay that you •had yourfelf feen thofe experiments of Dr. (H- — -is's,. I muft beg the favour of you to tell .me v{hQt tbo^Q co7nmon experhr^nts wcre^ and by what authority you took upon yourfelf to fay, that the experiments you then law were the

fame with thofe of Dr. H s's, which you

had not feen : for, if I remember right, I ihew- ed you federal at that time, which were not mentioned in my firll volume.

• I have not heard that Dr. H— — s himfelf .charges me with having taken any thing from

him ;

* This was on the 23d of May, 1 775.

(0

Philofophical Emphicifm.^ 5

him; and with refpe^ to .the principal thing which J then ihevvad: you as new, it is inipoiri- ble that he fhould have claimed it 5 when, as I immediately told you, in the prefence of the- gentlemen abovementioned, it was but a little time before, that he had hefitated to admit the fads when 1 mentioned them to him 5 as, in- deed, I fhould have done mylelf a little before that, had any other perfon mentioned them to me ; the difcovery of them haying been per- fedly accidental, and affording no foundation for merit \yhatever.

sicli

HA

What he advances in his printed Syllabus is' the X'ery reverfe of my ideas on that fubjc^, and, in my opinion, is contradided by the ex- periments I then fhewed you. Indeed, it is

now abundantly evident, that Dr. H -s and

myfelf have hardly one common idea concern- ing air ; fo that if he be right, moft of my difcoveries are, what he has thought proper to call them, mere conceits \ and if i be right, his general dodrine is entirely chimerical and falfe. On this account, it is hardly pofTible that we fhould have taken any thing from each other -, except that he has adopted fome things con- tained in my firjl volume^ the fecond edition of which had been publilhed fome time before I had fo much as heard the name of Dr. H ^s.

B

In

^ Philofophical Empiricifm.

In this bufinefs, therefore, there mufl have been fome miftake (I hope not yours) which I am toJd it behoves me to inquire into. I am, with real regard.

Dear Sir,

Your very humble Servant,

Shelburne-houfe,

'Nov. 30, 1775. J. Priestley,

This letter I delivered to the Dodor at the Royal Society, on the day in which it is dated ; and the fame day, having received farther in- formation concerning the bufmefs, I wrote the following letter to Dr. H s.

Sir,

I have this day been informed, from un- doubted authority, that you have charged me with having publifhed, as my own, expe- riments, what I learned of you ; but though I have inquired of feveral perfons, who all agree in the fa6l, of the charge in general, none can tell me what the particulars of it are. I muft, therefore, beg that you would yourfelf inform me concerning them. A man of honour would have given me an oppor- tunity

Philofophical Empiricifm, '*}

tunity of vindicating my felf, before he had publifhed my accufation to others.

I am, Sir,

Your very hurnble fervant Shelburne-houfe, Nov. 30, 1775. J. Priestley.

The next day I received the following an- fwer from Dr. Brocklelby, and on Dec. the 3d, that which follows from Dr. H — — s.

Dear Sir, The experiments which I faw you inftitute at Shelburne-houfe appeared fo nearly the fame with a greater variety of fuch as I had ' feen in three courfes of chemiftry given by

Dr. H s, that, in juftice to my abfent

friend, I was urged, poffibly, to violate the laws of hofpitality, by declaring in the in- ftant, that none of the divers experinients you was then pleafed to exhibit were novel to me, except one concerning the Swedifh fluor.

Whether your difcoveries were prior to thofe of Dr. H s I muft leave to the determi- nation of others, it being, at this diftance of time, not eafy for me to afcertain to whom the priority of thefe claims belongs.

B 4 When-

^ Phil'ofophicat Empiriclfni^

Whenever this fubjecl has occurred in coin verfation, I have repeated what, f Had^, icitbf the iT\ofl pure intentions, declared in your pre- fence ; never apprehending you had caufe of offence, on fubjefbs wherein, by your own de- claration, you and Dr. H— — s entertained nQ- tions totally repugnant.

I fincerely wifh your philofophical improye- ments may obtain every merited honour: at the fame time 1 fliould feel myfelf unjuft ta fupprefs candid applaule to another gentleman, of whofe unwearied labours I have been a conftant >yitnefs more than a year and half paft. I am, with great r^fpect.

Dear Sir,,

Your moft obedient humble fervant

Norfolk-Street, 30 Nov. 1775. Richard, Brocklesby,

Sir, Nine months are elapfed fince I informeci vou, in plain, but the lead offenfive terms, that I wiftied to decline your vifits and cor- refpondence. You know the motives of a condqd fo candid, and with all fo repugnant I to

Thihjo-phical Empmcifm, 9

$0 my own intereft as a teacher. You now cannot lerioufly expe6t that I fhould repeat what you well know— that I fhould enume-: rate the things \vhich you aflume as your own, and which I had previoufly Ihewn and taught.

If any other gentleman had propofed the queftion contained in your letter, an anfwer would he necefiary j and I {hould commence it with comparifons of the dates of Dr. Prieftley's rapid publications, with tlie plates of my courfes of chemiflry.

For the future I will add to the charge againft you, that you have treated others as you have treated me ; and that your origina- lity in experiments confifts chiefly in the knack of rendering the phenomena, which all prac- tical chemifts have obferved and underftood, perfedlly myfterious and furprizing to others.

The only part of your letter, then, which requires an anfwer, is that wherein you hint that a man of honour would remonftrate to you, inftead of uttering the truth to others. Herein your notions of honour and mine dif- fer widely. I fpeak freely fuch truths as can be well vouched, but I never remonftrate, ex-

cepi;

10 Philofophical Empiricifm.

cept when a gentleman has inadvertently ofr fended.

I am, Sir,

Your humble Seruant Greek-ftreet, Soho, ^

Dec. 3, 1775. Bry. H-T--^s,

This letter (the grofs rudenefs, manifeil lliiiffling, and abfurdity of which, .will hardly imprefs my reader in his favour, and may, perhaps, make fome of his friends blulli for him) giving me no fort of fatisfac- tion with refpefl to the particulars of the charge of which I was in queft, I thought it neceSary to interrogate Dr. Brocklefoy more dillin6lly •, efpecially as he owned that he had of himfelf only, and not, as I had imagined, through the medium of fome third perfon, aflerted the identity of my experiments with

thofe of Dr. H s. I therefore fent him

the following letter, which brought an anfwer not more fatisfadory than the former, except that 1 was convinced by it, that nothing more fatisfadory could be procured on the fubjed.

Dear Sir,

I am glad to find by your letter, that 1 am to look no farther than to yourfelf for the evi- dence

Philofophical Empiricifm. ii

denee of the experiments I fliewed you at Shelburne-houfe having been the fame with

thofe Dr. H s had exhibited before that

time. And as you have not yet anfwered the queftion which I took the liberty to propofe to you (fmce experiments that appear nearly the fame with others, may, in reality, be ef- fentially different from them) and as Dr.

H s himfeif has refufed to give me any

fatisfadlion on the fubjed, I am obliged to repeat my requeft. But to make the trouble of fatisfying me more eafy to you, I lliall be a little more particular in this letter than I was in my laft.

The firft experiments that I had the plea- fure of fhewing you were thofe by which I Ihew in what manner to apply the teft of ni- trous air, to afcertain the purity of atmofphe- rical air, which is defcribed in my firft vo- lume, and the manner of firing inflammable air with, or without common air, which I learned of Mr. Cavendifli. None of thofe, therefore, are to the prefent purpofe. After this, the only thing I exhibited, which I de- clared; to have difcovered pofterior to the pub- lication of my firft volume (exclufive of the experiments on the fluor acid^ which you ac- J^nowledge you had notfeen with Dr. H— — ^s)

were

12 Phiiofothjcal Empinafm,

were experiments relating to quite another kind of air.

Now as, by your own account, you were- able to pronounce immediately upon the iden- tity of thofe experiments with thofe you had

feen of Dr. H s's, and have repeated the

fame thing whenever the fubjeft has occurred in converfation fince, you mull be able to tell me now what thofe experiments were. Pleafe, therefore, to anfwer the following, queftions.

1. From what materials did I tell you tha]^ I procured that air ?

2. What name did I give to it ?

. 3. What were the peculiar properties of it ? .

4. In what manner did I demonftratc thofq properties?

I propofe thefe queflions fo diflindly, be- caufe unlefs you can anfwer them with preci- fion now, it cannot be thought that you were able to pronounce on the fubjed with lufEci- ent precifion before. Pleafe alio to tell me». as nearly as you can recoiled, how long is was before you faw the experiments above- mentioned

Philofophical Empiricifm. i^

mentioned with me, that you had feen the

fame with Dr. H s. Was it in his firft,

in his fecond, or in his third courfe ? for you mention three of them.

I will add, that the experiments which I exhibited to you were fo very remarkable, and 4b exoeedingly different from any others, of whicli any printed account was then publifli- •ed, that they muft have fbruck you in a par- ticular manner; and therefore you cannot but remember pretty aearly when it was that ■you firft faw them. I do not even think it poflible that they could have been exhibited at any public lefture in London, without oc- cafioning io much converfation among philo- fophers upon the fubje<5l, that I muft myfelf "have heard of them.

You need not make any apology for what you call viQlciting the laws of ho/pi tality, pro- vided you have fcrupuloufly obferved (as I am fully fatisfied you have done intentionally) the much more important laws of truth.

I am,

Dear Sir,

Your obedient humble Servant,

Shelburne-hotife, J. Priestley.

Dec. 4, 1775.

r>4 PBilofophical Empiridjm.

The Answer. Sir,

Your letter found me yefterday fcnt for to attend a lady ill of a fever at Guildford, and I did not return till this day noon, and in the firft moment of leifure, at lo o'clock at night, I now fit down to anfwer your letter, and I hope it may clofe our correfpondence on this fubjedl of controverfy, from which my temper is truly averfe.

I muft, in the firft place, fubmit to your re- confideration the following paragraph in your letter. " I propofe thefe queftions fo diftind:- " ly, becaufe, unlefs you can anfwer them " with precifion now, it cannot be thought,, *' that you were able to pronounce on the " fubjei5l with fufricient precifion before."

Hereupon, I take leave to obferve, that this conclufion is not admiffible, and that an opinion given in the inftant, and in your pre- fence, whiift the facts were before me, may have been altogether juft, although, at the diilance of many months (having feen, both before and afterwards, frequent and various combinations of fimilar experiments) I do not perfedly recoiled: every experiment then made, nor even all the new names you might have 4 given

Philofophical Empiridfni» i 5

given to appearances, which were familiar td me. I will not, therefore, attempt to anfwer the following queftions, which might involve me in fubtilties, or at kclft lead you to further perplexities, rather than clear tip the fubjedt.

' i. From what materials did I tell you, that I procured that arP'?-

2. What name did I give it ?

3. What were the peculiar properties of it ?

4. In what manner did I demonflrate thofc properties ?

But your 5th and lafl queflicm I will moil

readily anfwer. Dr. H s, in the firft

courfe of Chemiftry, June 1774, read his firft ledures on the fubjefts of air, fixed air, in- flammable air, the elaftic matter of acids, of alkalies, of phofphorus, ethers, and on p^lo- gifton, light, and fire ; on all which fubjefts he entertained (to the beft of my recolledion) the opmions he now advances, and hefupport- ed thefe opinions by various ftriking experi- ments, and by fome of thofe you fhewed, among others. And having feen the manu- fcripts from which he read in his firft courfe,

and

io Philofophical Empiricifm,

and whicia -Were voluminous, I am perfuacled that very many of his conclufive experiments were made at a period anterior to his Hrlfl: courfe. Thus far 1 fpeak what is known td others of his pupils -, but of my Own know- ledge I can affirm that, in private converfa- tion, he has repeatedly difcuired, and debated thefe fubjefts with me, fo as to have convert- ed me from my formerly-imbibed opinions of fixed air, inflammable air, and phlogiftonj for feveral years previoufly ; and I remember particularly his converfatioh^ concerning Mr. Woulfe's method of faving the acid, ethereal, and alkaline elaflic fluids, publi£hed years ago j in divers of which converfations he attem-pted to convince me of the nature of thefe fluids, al- ways expreflofig the higheft veneration of his favorite philolbpher Mr. Cavendifli, whofe genuine taflie and precifion in conducing ex^ periments, and his philofophical indu6tioD% iie was often wont to fay were truly worthy of a difcipk of Bacon, or the immortal Newton % and that modern Philofophy, in his opinion, owed more to Mr. Cavendiih, than to any other man now living, except Dr. Franklin. In confequence of a variety of .thoughts, fug- gefted to him, by a careful perufal of Mr.

Cavendilh*s works, Dr. H- s„ in his firft,

as well as in his fucceeding courfes, 'broughr experiments conclufive with me, fo that I

feel

Philofophical Empiricifm. , . ly

ftel myfelf as much convinced, as the nature of thefe recondite matters admits of, that his notions of elaftic fluids, diftintfl from air, are founded in nature, and that acid, whether vi- triolic, muriatic, or vegetable, is an elaftic fluid when detached, and that, even however com- bined with phlogifl:on, all thefe, together with the microcofmic acid, may form a combufti- ble vapor, incoercible in the ordinary procefles of chemiftry, but which may be detained in proper vefiTels to ferve for experiments.

And I apprehended that fuch combuftible vapour (whether in making ether, or metal- lic folutions, or by decompofing fulphur with iron filings moiftened with water, or if even Knuckel's phofphorus, formed or detached by various other artifices, devifed by Dr.

H s, to confine phlogifticated vapour)

will burn in open vefiTels, in that part imme- diately in contaft with the atmofphere ; and 1 learned that thefe elaftic vapours when mixed in various proportions with common air, and approached by flame, Ihall difplode, and caufe a loud noife in going off^, and leave the air newly combined with fome principle that was in the vefl^el, fo that it foon fhall become fixable air ; in almoft all which he candidly re- peated his obligations to Mr. Cavendifli.

C The

iS Philofophical Empridfm,

The acid of nitre he all along confidered nearly in the fame manner as the other acids, with this difference only, that with the ele- mentary acid of nitre he ever imprefled the notion, that fomewhat which operates like air in all combuftions, and on phlogiftic bo- dies, or poOibly that air itfelf is combined. This too he has fhewn by experiments with nitrous acid and fpirits, oils, phofphorus, me- tals, &c. with all which vifible fire is pro- duced by his curious proceffes. And with a number of other bodies only heat, not fire, was produced.

He alfo frequently remarked the phenomena of mixing air with the nitrous vapor, which iie did in a very fimple manner, by only un- ftopping the bottle of his flrongeft nitrous acid in a quiefcent air, or remarking the like appearances in a procefs for pirmiefon, and ^^veral others.

He demonftrared that lal-ammoniac is made by combining volatile alkali wich muriatic . acid, and that this combination takes place in the great elaboratory of nature, in the volcanos of Etna, and wherever tlie. that fait is found in nature, as well as the procelTes of art for making this great article of commerce. And that in every poffiblc combination of acid va-

1 por

Philafophical EmpMdfifi. 19

"por with volatile alkali iri vapot fome neutral fait is produced. This he alfo explained by- forming at his ledures the elallic Vapot of ftrong acid and alkali.

Now having fairly given you this minute de- tail of fuch experiments made in Dr. H s's

courfe of lectures, a{k yourfelf if thofe you was pleafed to exhibit at Shelburne-houfe could appear altogether novel to me : for I apprehend your giving other names to fuch experiments, or ufing a fmaller or neater apparatus, did hot conftitute any important new difcovery;

** I will rlow end this very irkfome bufihefsi with one remark, that the mod fublime philo- fopher, who weighed diftant worlds as in a balance, and taught wondering mortals many of the moft fecret laws of hatLire^ as they operate on all matterj had fo great an averfion to dealing in controverfy, that 1 know, oil good authority, the world had like to have been deprived of the Principia, when he ap- prehended the publication of that book might involve him in any akercatioh with his co- temporaries i whim, in our days> on the con- trary, I amj againft my will, drawn into this long and tedious letter, to fettle whether a philofopher, high in modern rank, has the C 2 exclu-

20 . . Philofophical Empiricifm.

exclufive privilege in this or that phlogifticated vapor of the mineral, vegetable, or animal kingdoms. I know this is my firft literary diipute, and that it fhall alfo beniy laft, fori will fay no more, but that I am,

Dr. Priestley's

Humble Servant,

Norfoik-ftreet, 5th Dec. or rather 6th, Rich. Brocklesby,

at 2 o'clock morn.

From this letter it is but too apparent, that Dr. Brocklefby had not been able to diftinguifli what he faw with me from what he had feen with Dr. H — — s, and therefore that no fort of ftrefs can be laid on his teftimony. Had I urged him any farther, and (like Daniel with refpeft to Nebuchadnezzar) told him what he himfelf had quite forgotten, or rather had never rightly apprehended, viz. that he had feen with me a fpecies of air which I had procured from earth and fpirit of nitre*, and Which I had c^WtcX dephlogifiicated air -, being about five times as pure as common air j that a moufe had lived in a quantity of this kind of air five times as long as it could have

done

Philofophical Empiricifm. 21

done in an equal quantity of common air; that a candle burned in it with five times as great fplendor as in common air-, and that when a quantity of inflammable air was fired in it, the report was even fifty times louder than it was in common air -, ftill, fituated as he was, and fo little able (as his letter de- monftrates) to diftinguilh what he faw, he might have perfifted in what he had incau- tioufly once afferted, and therefore, without the lead violation of integrity, might have affirmed that he had feen all thofe things with

Dr. H s ; though according to his own

Syllabus, there could not, in nature, be any fuch thing. But 1 was , far from wifhing to pufh the Doftor upon this precipice. Ail I had occafion for was barely to fet afide his teflimony againft me, for which his prefent utter ignorance- of what he faw with me (though things of fo very remarkable and ftriking a natui-e) is abundantly fufficient.

I mull not clofe this article without con- gratulating Mr. Cavendifli on his acquifition of the profound admiration of fo competent

a judge of philofophical merit as Dr. H s.

But though he knows that I believe him to be very deferving of the encomiums that Dr.

H s, and Dr. Brocklefby have paid him,

I rather think that his feelings upon the occa- C 3 fion

^2i ^hihfophical Empmcifm.

(ion will not be very different from thofe of Dr. Franklin, in a fituation that will be men-, tioned hereafter, and that it would have given him more pleafure laudari a laudato viro^

Finding myfelf, after all the pains I had taken, to lie under an accufation of fp very vague and undifcribed a nature j having en- deavovired in vain to procure a copy of my in- di^ment, either from my acciifer, or the wit- vitis ; and not knowing how far this un- known charge may extend, 1 muft endeavour to make it out myfelf, in the b^ft manner that I can, from fuch materials as the Recollec- tion of the whole of n^y intercourfp with

Dr. H -s can fupply me with ; for which

purpofe I muft go over it all, and efpecially our conyerfations on philofophical fvibjec^ts. This plan m\\ oblige me to mention feverat things which muft appear to his difadvan- tage, and which I ihould not ptherwife havti mentioned. But my fituation is fuch, as does; not allow me to have recourfe to any other method, more favourable to him. Had his accvifation been dijiin^f^ and confined to any certain number of articles, I fhouid haye an^ fwered to thofe articles only.

SECTION

Philofophical Empiricifm, 23

SECTION II.

A general account of my inter courfe with Dr. U^ — s.

It was fome time in January, of the pre- fent year 1775, that, being at the R^yal So- ciety, I firft heard the name of Dr. H s

from Dr. Brocklefby, who told me that he was a perfon highly deferving my notice, as an excellent chemid, and efpecially as one who had made feveral difcoveries concerning air, I afked him what particular difcove- ries, of value, he had made. He replied that he had difcovered fixed air to confift of common air and phlogifton. I anfwered, that that was very far from being my idea of the rnatter, and freely intimated to him, that a perfon v/ho maintained an opinion fo contrary to all probability could not be much of a phi- lofopheri, or have given much attention to the fubje<a. Still, however, the Dodlor prefled me to be introduced to him, and, with much relu6tance, as he can witnefs, I did, at length, confent to dine with him on the day that Dr. H- — ^s was to open his next courfe of lec- tures, which was the 6th of February fol- lowing, that we might go together.

C 4 In

'24 Philofophkal Empiricifm.

In the mean time having inquired of a very refpeftable friend whether he knew any thing

of this Dr. H s, whom Dr. Brocklelby

had recommended to me, he advifed me to have nothing to do with him. Upon this I gave oyer all thoughts of attending his le(fl;ure> as feme of my friends well knov/. However, iny evil deftiny, aided a little by curiojity^ and fuch a defire of knowledge, as milled our firft parents, helped mQ, at length, to get rid of my fcruples; concluding that, though Dr. H — — s certainly knew very little about air, he might be what is called a good chemifl \ and with fuch a perfon I'had long willied to form forrre- Acquaintance, being confcious of my own deficiency in that kind of knowledge.

Accordingly, after dining with Dr. Brock-, lefby, on the day mentioned above, I was in- troduced by him to this extraordinary man, who received me with marks of the greateft deference and refpedl-, and put me not a little to the. blufh by introducing his compliments to me in the courfe of his lefture, as well as into his converfation,

Upon telling Dr. Franklin, the next morn- ing, where I had been the evening before, he told me that he had- once attended one of thofe introdudory ledures of Dr. H — ■ — s (four of

which

Philofofhical Empiricifm. 25

which he gave gratis in this courfe) and faid, " Pray, did he not pay you fome compliments " in the courfe of his ledlure ?" I faid yes. He replied, " I thought he would, for he paid me " fo many, that I was quite afhamed, and *' really had a more unpleafant feeling, "Trtfln I " had during all the time of Wedderburne's " lying abufe of me, before the Privy-Coun- *' cil. I believe, however," added he, " that the " man may be a good chemift, and his ac- " quaintance may perhaps anfwer your pur- " pofe." Serioufly, as this great man is now engaged, he will fmile when he fees an account of this incident in print, as well as at the ri- diculous conteft into which I have been drawn.

In the manner in which Dr. H s deli- vered this lefture there was an appearance of modejly and diffidence, with which I was much pleafed ; and, looking upon him as an induf- trious and ingenious man, wholly devoted to his profefTion, who had expended vaft fums of money on his apparatus and experiments -, and feeming, by his looks, to have v/alled his conftitution, as well as his fortune in thefe purfuits, I really had a ftrong feeling of com- paflion for him, and made a point of recom- mending him to my acquaintance, as a modeft and fenfiUe kSiurer -, and this I did pretty

warmly

a 6 Philofophical Empiricifm.

warmly (as I am known to be apt to do, whenever I conceive a liking for any per- fon) and this feveral of the nobility, other perfons of large fortune and diftindion, and my philofophical and literary acquaintance in general, can witnefs. Nor h^ve 1, to this day, taken the leaft pains to unfay any thing that I then faid in his favour, or have faid anything elfe to his difparagement j except when I have been particularly urged to it, by fomething occuring in converfation, that made it neceffary for me to do it, in order to my own vindication, Indeed, I was afhamed to retraft what I had, in my incautious zeal, fQ warmly advanced,

In our converfation after the k<5lure. Dr.

H -s, in the prefence of Dr. Brocklefby,

exprefled, in the ftrongeft manner, the fenfe he had of the honour that I did him by my at- tendance on his ledlure, and in a very hand-, fome manner made me a tender of his bell fervices, in cafe he could be of any ufe to me. I told him that, not being a praftical chemift, having never had a proper laboratory, or iton much of the ufual procefles, J wijfhed to have an opportunity of obferving fome of them : but that I more efpecially was in want of che-^ fnkal articles, fuch as I could not eafily pro- cure at the ihops, or on the preparation of

which

Philofophical Empiricifm. 37

which I could not abfplutely depend ; and therefore Ihould think myfelf very much obliged to him, if he would fupply me with iuch things as I might occafionally want in the prolecution of my experiments, and that I fhouid very thankfully give hin^ whatever price he chofe to alk.

This he readily promifed to do, and added, jhat if I would do him the pleafure to call upon him, 1 Ihould be fure always to find him at home before dinner, and that there would never fail to be fome procefs or other in his laboratory, which I might examine at my lei- fure. In return for this obliging offer, I de- fired that he would give me the pleafure of his company at Shelburne-houfe, where I would endeavour, in return, to entertain him with fuch experiments as I made. But this, al- ledging he had no time to fpare, he civilly Reclined.

From this time I called upon him occafion- ally, took of him fuch articles as I wanted, always gave him his price (concerning which I was intirely ignorant; and always expreffed myfelf much obliged to him. I feldom flay- ed with him more than a quarter of an hour at a time, fometimes not more than a few mi- nutes J being in hafte to make my experiment

with

2 8 Philofophical Empiricifm.

with the fubftance that I procured of him : and I do not think that ail the time I ever fpent with him exceeded tour or five hours. Indeed I very feidom {laid any longer than while he was either finilhing what 1 found him about, or while he was employed in weighing, making up, and labelling the feveral articles I took of him. Exclufive of this, I do not think that 1 fpent more than a fingle hour v/ith him in all; my own time being as fully employed as his. And the time I fpent with him in this manner was chiefly out of regard to civi- lity and propriety •, thinking it would not be decent to make the fame ufe of his laborato- ry, as of a common Ihop ; always running away the moment that 1 had got what I wanted.

The fecond, which was the laft time of my attendance on his ledure, I put myfelf to fome inconvenience to do it, and really did it from no other motive, but that I thought I fhould ^oblige him by my countenance •, and though I had not the vanity to think that I was doing him all the honour^ and all the -pleafure^ that he told me my vifits would do him, . I was willing to give him the gratification that he feemed to promife himfelf trom them.

At one time I was induced to make a longer flay with him than ufual, by the coming in of

Mr.

Philofophical Empirieifm. 29

Mr. Delaval, whom I had not bad the pleafure of feeing before, and whom I was much pleafed with having this opportunity of feeing. And I mention it to give my readers fome idea of the manner in which he, at that time, ufualiy treated me, that they may compare it with the ftiie of his letter to me.

Upon mentioning my name to Mr. Delaval, which he did in a manner that feemed to fhcw he had fome kind of fatisfaftion in doing it, he faid, ■" You fee, fir, all men of note find " me out at laft," or words to that effed. AI- fo, when, in the courfe of one of our con- verfations, I had occafion to afk him whether, he happened to have a copy of my book at hand, he replied, with that formality, of which all who are acquainted with him know that he is capable, " Do you think 1 could poffibly be " without fo very capital a performance upon " the fubjed" ?

This compliment was, to be fure, awkward enough j but I did not take it to be meant iro- nically^ as there was nothing elfe in the con- verfation that could bear fuch a conftrudlion. How he can now reconcile thefe encomiums with his calling the principal difcoveries con- tained in the fame book mere conceits^ and with his faying that what I have done confifts chiefly

m

56 Philofophkal Empiricifnt.

in th£ knack of rendering the ■phenomena which dll fraiiic(^l chemiJi'S (arid himfelf, no doubt, who is at the head of them all) have obferved and underjlood, perfeBly myjierious and furprizing to others (that is, thofe who are not pradical che- mifls) I leave to him^ as a pra61:ical chemift, to make out. After thefe compliments, was it pofTible for me to imagine that my company could be fo very tirefome to him, as he has fmce affirmed ?

I had riot called upon Dr. H- - s more than two or three times, before I began to perceive that his appearance of modejiy, and his extreme deference and complaifance^ began to wear ofFj fo that, like the fox with re- fpe(5t to the lion, in the fable (if he will like the comparifon) he began to be much more at his eafe, and his natural character and turn of mind became fufficiently confpicu- ous. For, from an extreme of deference and refpeft, he advanced, by degrees, to fuch a pitch of ajfurance, and fuch airs of cunceit, and felf-importance, as I have feldom obferved in any man ; perpetually boafting of the dif- coveries he had made (but without mention- ing any of them) complaining loudly of the great expencc he had been at for the fake of promoting fcience, and of the low illiberal tafte of the age, difcovered by his not re-

Philofophical Empiricifm, 31

ceiving proper encouragement •, fpeaking con- temptuoufly of other perfons of his profef- fion, and with particular indignation of many perfons (whofe names, however, he never mentioned) who had ftolen their difcoveries from him, without having made any ac- knowledgement of it in their publications *.

Such topicks, and fuch a turn of conver- fation, into which he was perpetually falling, gave me, I own, no very favourable idea of my new acquaintance. But ftill I made allowance for this conceit, and bore with it, as being, in fome mealure, incident tq perfons who give their whole attention to a fingle thing, in which they are allowed to excel, who have, not feeji much of the world, and who have, therefore, had no opporr.unity of acquiring that liberal turn of mind, which is the greateft ornament of true fcience.

* I always joined with Dr. H s In condemning this

kind of conduct, and affared him ihac whatever obliga- gadon I ihould be under to him, i fhould certainly ac- knowledge it ; and my book will prove that i have done fo in the ampleft manner. My feccnd volume, which is now printed oft, was written at a time when 1 was very far from being fatisfied with his condud, though I had noS heard of his cbims upon me. But though he has ufed me very unhandfomely, I have fome obligation to him for. the materials he allowed me to purchafe of him, and therefore I do net wifh to rzxvKd. what 1 have And.

I now'

32 Philofophical Empiricifm.

I now come to the cataftrophe of our ac- quaintance, of which he has given very dif- ferent accounts, and concerning which I have formed different conjed:ures, in confequence of viewing it in different lights, as I fhould do any* remarkable appearance in philofophy. As I always told him, when I applied to him for any fubftance, or preparation, what I wanted it for-, I Ibmetimes afked him whether he could not recommend to me fomething elfe that was likely to anfwer my purpofe better ; and fometimes he would tell me, and fometimes he declined it ; almofb always concluding the converlations we had upon thefe fubjefts with telling me that I muji attend a complete cotirfeof chemijiry. 1 always replied, that I had not time for it ; never fufpecling what he was aiming at all the while ; till, at length, upon his urging me on this head more ftrongly than before, and my telling him more peremp- torily than before, that I really could not fpare time for any fuch thing, he faid very abruptly, that " his time was fo much taken " up with neceffary bufmefs, that, without " meaning any perfon in particular, he was '' obliged to come to a general refolution, " to anfwer no ^quejiions hut fuch as he was paid " /(?r." This, in a moment, difclofed to me fas I then concluded) what I was aftonilhed I fliould not h ave difcovered before, viz. that 4 his

Philvfophicd ]tmpirmjht, §3

his little objed had been to get my fub- fcription for attending his coiirle. Difcon- certed as I was, I had the prefericie of mind to commend his refolntidn, as very neceffary for a perfon of his many engagements 5 and after this I called upon him no hiore.

fill this laft converfatioh, which was in his own houfe, while he was Ihaving himfelf, and confequently did not etigrofs any of his va- luable time, I had feen nothing in his beha- viour (making the reafonable allowances above-mentioned) that could give me offence, hor did I perceive any mark of his having conceived the leaft diilike to my vifits. Even this very laft time that I was With him, part of his Gonverfation was, to all appearance, very friendly. He then mentioned to me, particu- larly, Mt. Wilfon's hook on Phofphori^ and ex- prefled the ftrongeft difapprobation of his treatment of me in it; faying he hated fuch things among philofophers ; and added, that he had freely told a friend of Mr. Wilfon, who would be fure to tell him again, that^ befides the malice of the thing, he was quite wrong with refpecl to the fa6l.

Could I imagine that a man who talked 10 me

in this manner was, at the fame t/ime^ wifhing

to get rid of me } I therefore conclude, that

D his

34 Phihfophical Empiricifm.

his determination was occafioned by the con- verfation that immediately followed this, and by which he found that I abfolutely refufed to attend his ledlnre •, whether his view was merely to get my fuhfcription money, which I then imagined to be his objeft, as thofe of my friends to whom I told the flory caa witnefs ; or whether he meant to engage my attendance upon his lefture with a view to fomething farther, as I now conjedure, viz. that he might have the honour of being my inftrudlor, and thereby have a pretence for laying claim to all my experiments.

That I took up too much of his time, I am fatisfied is an after-invention ; and in his letter to me he makes no complaint of that kind, but alludes to fomething elfe, which he fays I / know, but concerning which I can only form conjedcures.

When 1 conlider every thing relating to this bufmefs, I cannot eafiiy fatisty myfelf with

any hypothecs to account for Dr. H s's

behaviour to me. He is a man altogether un- known to the world. He has not diftinguifh- cd himfelf by any philofophical difcovery that I have yet heard of, and the airs he may give himfelf in his clafs, or in converfation, are

nothing

Phitofophichl Empiricifm. 35

hothing to the world at l^rge. He may, in faft, be as great a man as Lord Bacon, Sir Ifaac Newton, or Mn Boyle ; and if his per- formances (hould correfpoiid to the idea that his printed Syllabut is calculated to give us of him^ he mufl. be a greater man than any of them* and indeed greater than all the three put to- gether. But then this cannot be known to the world, till his experiments, proving the dif- coveries that he has announced^ be adtually made, and an account of them he publifh- ed, which will require at leaft fome months (though before that time his fubfcrihers may have an opportunity of knowing whether he be, in fact, the great man that he gives himfelf out to be or not j and Ibme of them^ it can hardly be doubted, will have zeal or indifcre- tion enough to whifper the fame of their maf- ter, whatever injundion his modefty may lay them under) and during the time that I had the honour of his acquaintance, he had not fd much as announced his importance to the world ; for his famous Syllabus was not then publiflied i fo that even now, and miich more fo far back as the fpring of the prefent year, he mufl: be confidered as an obfcure per/on^ to whom, confequently, the countenance of a perfon more known to the world might be fup- pofed to be of ufe,

i) i Now,

^6 Philofophical Empmcifm»

Now, with refpeft to myfelf, whether it has come tome by inheritance, or by acquifition, juft or unjnft, whether it is owing to good fortune, or defert, it is faSl^ that I have been fome years in polTeflion of the mod re- fpeftable acquaintance that this country can furnifh •, and as it is almoft univerfally true of Englifli philofophers, that they are much more celebrated abroad than at home, this has, of courfe, been the cafe with myfelf as well as others, and, by fome accident or other, per- haps in a greater proportion with refpeft to me than moft others j in confequence of which, being naturally warm, and I will add conftant in my attachments, it could not but be much in my power to befriend any man in the fitu- ation of Dr. H s ; who, one would ima- gine, would, therefore, rather wiih to be brought forward by my friendfiiip, than rafhly make me his enemy.

I therefore frankly acknovvledge that I can- not clearly account for the facr, as a phenome- 7ion in human nature-, unlefs perhaps by adding to the conjedures abovementioned, that he may have been pradifed upon by fome of my enemies (for all men have enemies) or that, being poffefTed of an uncommon degree of conceit, and having but little knowledge of

the

Thilofophical Empiricifm, ^%y

the world and of mankind, to counterad the abfurd effefts of that prepofterous paffion, he has taken it into his head, that he Ihonld gain rhore by fetting himfelf up as my rival m philofophical reputation, than he fhould do by availing himfelf of my friendihip.

It appeared to me at the time, that hefufpe^ ed me not to be quite fin cere in what I had told him concerning my endeavours ta ferve him amongmy acquaintance, becaufe they did not im- mediately wait upon him, or attend his ledlure ; which was a very unreafonable expedlation. For a perfon who knows any thing of the world muft have been apprized that, recommendations of this kind can only operate flowly, and that fufficient time muft be allowed in all cafes of this nature. For, at the fame time that he told me that he was come to a refolution to anfwer no more queftions but fuch as he was paid for, he faid, " a greater mifchief could not be done " to a man, than to flatter him with falfe ex- " pe6tations of patronage and encouragenient." After this I refolved not to do him any more mifchief of this kind. But neither have I done him any mifchief of a different kind ; for I have never taken the leaft ftep to his preju- dice. But, with refpect to all thefe conjedt- ures, I can only fay with Logicians, valeant quantum vdere pojfunt.

l> ^ I (hall

'|S Philofophkal Empiricifm.

I fhall conclude this fedion with acknow- ledging that this affair has contributed not a lit- tle to lower iTie in my own eftimation, as I really imagined that my charafter was fuch, as could not but have been more refpedted by fuch a man as Dr. H — — s, and that independent of my recommendation of him, he would even have thought my philofophical communica-^ tions (of which all my acquaintance know me to be very liberal) a fufEcient recompence for the little fervices that he could do me,

SECTION

Thilcfophical Empiricifm, ^g

SECTION III.

^H account of what I faw^ or heard, of a philo' fophical nature with Dr. H s.

I fhall now proceed to recite the fubllance of all that I faw or heard, that bore any rela- tion to philofophy, in the very (hort time that

I fpent with Dr. H- s ; that the public

may form fome judgement of the probability of my having taken from him any thing that I have fince publifhed as my own. But really our converfation very feldom turned upon philofophy ; moft of the time that I was with him being taken up with complaints of the vaft expence he had been at, and the little profpe(5t that he had of getting his capi- tal back again : tho' I muft do him the juftice to fay, that he always fpoke with the greateft contempt of money, calling it, to ufe his own words, mere dirt and trajh, compared with philofophy. There only remains fome little doubt, whether, in this, he had a view to his own money, or to mine.

Of his firft lecture (which, of courfe, con- lifted of introdu(5lory matter, proper for be- D 4. gin-

4i® Phihfophical Empricifm,

ginners) I remember nothing but his produc- ing a variety of diagrams, in order to explain the nature of chemical attradlion and repulfi- on, which he feemed to do with ingenuity enough.

In his fecond ledture, he did very little be- fides attempting to exhibit my experiments or\ alkaline air : but his apparatus being very ill contrived, he did notfucceed to his wifli. He was particularly embarrafTed in confequence of ufmgvery long glafs tubes, filled with quick- filver : but he told us that it was nece/Tary to have tlnem of that length, that when the mer- cury had fubfided to its natural level, there might be a vacuum in the top of the tube, for the alkaline vapour to expand itfelf in. But in this, not only is his reafoning very abfurd, but the fra^ice is liable to lead the experimen- ter into a miftake, with refped: to the real quantity of the air introduced into thofe long tubes. For my own part, I have feldom made ufe, for the fame purpofe, of tubes any longer than about nine inches, which are cer- tainly both more commodious and more ufeful ; and though the quickfilver compleatly fills thefe ihort tvibes, it is neceffarily displaced, and its room occupied by the afcending air or va-

PbikfQphical Empmcifm* 41

But though he fucceeded fo ill in this ex- periment on ^/r, I confidered that the fubjeft was new, and that it is only long pra(5tice that gives dexterity, and infures fuccefs in things of this nature. 1 cannot, however, forbear exprefling my furprife on this occa- fion, that he fhould adopt my own method of exhibiting the alkaline principle, if it on- ly tended to make " that myfterious and fur- *' prizing, which, in the method that was ^' known before to all practical chemifts, ♦* was perfedtly intelligible.'* In an addrefs calculated for fitidents, he certainly (houlcJ have adopted a method the leaft myfterious poUible.

.The firft philofophical converfation that I had with Dr. H s was of his own intro- ducing, in the prefence of Dr. Brocklefby, on his favourite topic of the conftitution of fifc- ed air^ on which we each of us gave our dif- ferent opinions ; he maintaining that it con- Jifts of common air and phlogifton, and t diffenting from that opinion. He maintain- «ed, however, that I had once been inclined to that hypothefis, or fomething like it, and appealed to my book. The book was then, ^nd is now, before the public, who may foon be fatisfied that it contains no marks of my Jiaying ever given the leaft countenance to an

opinion

4-t Phitofophical Empiricifm,

opinion fo evidently void of all probability. For philogifticated air wants almoft every dif- tinguifhing property of fixed air.

It is not imbibed by water, it does not turn the juice of turnfole red, it does not precipi- tate lime in lime-water (though, during the procefs, there is a precipitation of fixed air from the common air, which I difcovered, and gave an account of in my firft volume) and laftly, which makes as manifeft a diftinc- tion between thefe two kinds of air as any, they differ very greatly in fpecific gravity : for fixed air is confiderably heavier, and phlo- gifticated air a little lighter than common air.

The former was the difcovery of Mr. Ca-^ vendifh, and the latter was an obfervation of my own, mentioned in my firft volume, but more exadly afcertained in the fecond. Dr.

H s, however, not having attended to this

as he ought to have done, fays, in his Syllabus^ page 3, that, " phlogifticated air does not greats " ly exceed pure air in fpecific gravity.*' On the contrary, he will fee in my fecond vo- lume, if he thinks it worth his while to com- plete his fett of fo capital a work, that, the purer air is, the heavier it is, and the more phlogifticated, the lighter.

Before

Phikfophkal Empiricifm. . 43

Before Dr. H s lays claim to the diC

coverles of others, I think he fhould (hew that his mifiakes are his own. For his notion that fixed air confifts of common air and phlo- gifton is advanced by Dr. Rutherford, in his differtation on the fubjedt, and I am told was the opinion of Dr. CuUen, from whom Dr.

H s actually had it. In thofe gentlemen

the idea was very pardonable, the fubjed not having been fufficiently examined ; but it has been fo fully invefligated of late, that fo grofs a miftake concerning it is now abfolutely unpardonable; efpecially in a perfon who pre- tends to be a teacher of philofophy, and who is a fupercilious cenfurer of others.

Our next converfation, which was likewifc begun in the prefence of Dr. Brocklejfby, was qn the fubjeft of acids in the form of air. I told him that I had purfued what I had before difcovered on that fubjeft much farther ; hav- ing, particularly, made many experiments on the vitriolic acid air, which the readers of my fecond volume will fee were begun ,at- Mr. Trudaine's in France, and compleated prefent- ly after my return to England, before I had fo

much as heard of Dr. H s ; and that I

only wanted proper fubftances from which to expel the other acids in the fame fimple form, and a proper fluid to confine the nitrous. For

the

44 PhiUfophudl Empiricifm,

tfe^ vegetable mid air, he mentioned fevcral things which he thought would anfwer, and among others, a cmcentrated vinegar, of his own preparing, which 1 took, as the cheapeft <S^ them ; and by the help of it I immediately made the experiments defcribed in the fecond fedion of my fecond volum.e, acknowledging, as will there be feen, from whom I had the prepara^ tion.

After this, I was a little furprized, when, in the laft converfation that I had with him, he told me, as a new thing, that he had difcovered fh'e vitriolic acid air. I replied, " Do you not *' remember that I told you that I had done " the fame, the very firft time that I was in ** your company, and that I had materials for " a pretty large feftion on that fubjed, in- ♦* tended for my fecond volume?" To this he made not one word of reply.

In our firft converfation on the fubjecH: of acid air, I afked him whether he could fijid me any fluid fubftance that would not be af-* fe<5ted by the nitrous acid, which my readers will know to have been a great deftderatum with me. After fome paufe, he -told me he could, artd mentioned lees wax. But upon trying it with the llrongeft nitrous acid that he him- felf could procure me (and by which he faid -•- it;

Phikfophical Empmcifm» 45

it would be the leaft affedled) it was all diflblved by it, when it was a little heated, arrd there- fore did not anfwer in the leaft. I told him of the failure of this experiment •, upon which he faid he believed that he didknow what would anfwer, but he did not tell me. 1 imagined that he intended to profecute the experiment himfelf, and therefore I urged him no farther on that head.

While we were talking on this fubjed:, he {hewed me his procefs for making fpiril of nitre^ which was then going on, to prove that there is much air in that acid. But I had not time to confider what I faw, and I can give no good account of it. My own experiments give me a very different view of the fubjeft; and when I attended a courfe of chemical lec- ' ttires, delivered at Warrington, by the inge- nious Mr. Turner of Liverpoole, I was one who alTifted in making a quantity of fpirit of nitre, in a manner not fo expeditious, indeed, as that which 1 fuppofe is now generally ufed, but in which I am pretty confident there was no opportunity for any common air to get into the compofition of it. I wifh, hov/ever, to examine this procefs more particularly, and I think myfelf happy in having, for this, and other chemical purpofes, made more than one

acquaint-

4^ Philofophtcal EMpiriciffH,

acquaintance, by means of whom I fliall foon be able to gratify myfelf in this rerpe(ft.

At one time that I called upon Dr. H s,

he had a procefs going on by which he told me that he procured the fedativ-e acid, and I think he likewife faid, in the form of air. If he can fhew any fuch acid air, it is entirely his own. I have no fort of pretenfion to it. On the contrary, I am at prefent inclined to believe that there is no fuch thing*

As to the experiments which 1 have made on the fuor acid, I queftion whether I had fo much as begun them at the time that my ac- quaintance with Dr. H s terminated.

Thefe I was enabled to make by means of Mr. Woulfe, without whofe generous affiftance I could have done nothing on the fubjedl, as my narrative will fhew.

At the time of my introdu(flion to Dn H s, I had the greateft part of the mate- rials for my fecond volume, and I told him I Ihould foon make another publication on the fubjeft of air •, but that I wanted to complete two courfes, viz. on the extra6lion of air from various fimple and compound fubftances, by a burning mirrour in quickfilver^ and alfo by a mixture of fpirit of nitre j and 1 had feveral

preparations

Philofophical Empiricifm* . '47

preparations of him for thofe purpofcs, as my narrative will witnefs. Having got an ounce of mercurius cakinatus per fe^ of Mr. Cadet, while I was at Paris, for the piirpofe of my experiments on dephlogifticated air, which were begun long before that time, I would have had

fome of Dr. H s ; but found that (tho*

.he afiured me I had every thing of him at prime coil) he could not afford it fo cheap as Mr, Cadet. I therefore defired him to make me a quantity of red lead^ from which fubftance I had got air about five times as good as com- mon air. When I firft mentioned this kind of air to him, he faid, " How do you know that it is fo pure ?" I told him it appeared to be fo both by the teft of nitrous air, and alfo by a moufe actually living in it five times longer than in an equal quantity of common air : to which he made no reply.

The firft time that I faw him after I had got the red lead, which he had made for me, he faid, in the following identical words, " You " get no air from red lead." I told him 1 did, and even air five times as good as com- mon air, fuch as I had mentioned to him be- fore ; but, faid he " you get no air from the *' red lead that I made for you." I told him I did, and air of the fame kind, though in a very fmall quantity, After this it is impof-

. fible

4!^ Phikfophicat Empmajkt.

fible that he ftiould have any preten lions to the difcovery of dephlogijiicated air, which is the only difcovery for which the evidence of Dr. Brocklefby can be pretended, and eveti ihat pretended evidence has intirely failed him*

I firft difcovered that I could make de- phlogifticated air, and confequently commofi air, from fpiric of nitre and earth, when I was at Calne, on the 30th of March tfy5 \ which is a difcovery that direftly overturns

Dr. H s's dodbrine, as laid down in his

Syllabus, which does not admit of the con- vertibility of either earlb, or acid, into air. Upon my return to London, after I had fent my letter upon that fubjedt to the Royal Society, 1 told him that I now knew whaC common air was, for I could actually make it myfelf j and at the fame time I mentioned the compofition. To this he made not one word of reply. Now the air which I fliewed to Dr. Brocklefby, and which, he aflerts to have been the fame with fome that he had before feen in Dr. H-— < — s*s coUrfe, was this very kind of air ; having been made with different kinds of earth with fpirit of nitre.

Now that Dr. H s Ihould aftually have

made a fpecies of air, the compofition oE .which, according to the doflrine of his fyl-

labusj

Phiiofo'phicai Empiricifm. 4^

labus, juft now publifhed, is abfolutely im- pofTible, I think my readers muft deem to be a little extraordinary. In fliort, if this difcovery concerning the conflitution of at- mofpherical air, be not my Own, nothing that I ever did can be fo ; and if it be not fuffi- eiently proved by thefe confiderations, nothing of this kind is capable of being proved.

With refpefl to this miftake, however, as well as that concerning the conftitutibn of fix- ed air. Dr. H ^s has nothing to boaft ; for

the opinion that he maintains on this fubjedl is the very fame that has always been maintained by almoft every body except myfelf. But fo clear are the proofs that I have produced of it, from aAuai experiments, that I will ven- ture to fay, that if Dr. H- s himfelf does

not embrace it very foon, giving tip his fa- vourite fundamental doftrine of the elementary nature of air^ he will be as fingular in his opi- nion, as I have hitherto been in mine. Com- plete as his knowledge is of all the /even ele- ments of nature, Gomjprehending the omne fci~ bile of natural knowledge, his ipfe dixit, de- livered in his oracular fyllabus, is not of fo much authority, except perhaps with himfelf^ as that of fa6t zind experiment,

£ Sq

^o Philofophical Empiricifm,

So much is Dr. H s's dodlrine on the

fubjedl of air the reverfe of mine, which makes freedom from ■phUgiji on ^ exactly to correfpond to purity of ah\ that, in a converfation with me, he maintained that air might have too little^ as well as too much phlogifton. He did not think proper to explain himfelf on the fubjeft; and I can only aflure him that I know no fuch air. Let him produce it if he can, et erit mihi inagnus Apollo.

In the fame converfation in which I told Dr.

H s that 1 had difcovered the real confti-

tution of atmofpherical air, I told him that I thought I had alfo difcovered the compofition of fixed air. Upon this he fmiled, with a kind of triumph, faying, " You are convinced then, " at laft, that fixed air is a compound." 1 told him I was, becaufe I thought I had difco- vered in what it confifted, viz. fome modifi- cation of fpirit of nitre, and phlogifton, and .perhaps fome other principle. Upon this fub- je6l I am ftill in fufpence, waiting for more ex- periments. But allowing that I had changed my opinion, which 1 have never been averfe to acknowledge, I have not yet adopted his opi- nion^ viz. that fixed air confiftsof common air and phlogifton j fo that I am no convert of his^ but to myfelf the opinion being, as far as I know, peculiar to myfelf;. and therefore Dr.

H s

Phiiofophicai Empiricifmi £1

H "S can have no foundation for giving out, as I am informed he has done, that 1 have changed my opinion on the fubjecfl: of fixed air, in confequence of the converfation I had with himi

So. far was Dr. H- — ^s fhom being com- municative to me of his knowledge, that he was not always in the humour, notwithfland- ing his liberal promifes, to let me have the materials With which he could have furniilied me for my own expeririients, except on fuch terms as he faw I could not comply with. I once wanted a fmall quantity of fuch phofphorus as Mr. Canton made ; and as I faw that he had juft made a quantity^ of the excellence of which he boafted very much (as, indeed, he did of almoil all his preparations) I begged that he would let me have a little of it. He faid I fhould, if I would promife to give no part of it to any body elfe. 1 told him that I had no intention of communicating it to 'any body, but that t did not like to lay myfelf tihder the obligation of fuch a promife ; and therefore I had none^ Going to work myfelf, and following Mr. Canton's direftions, I found no difiiculty in making it fuiliciently well for my purpofe.

E 2 SECTION

Philofophkal Empiricifnu

SECTION IV.

Ohfervaiicns en Dr. H s's Syllahus, as far

as ii relates to the do^rine cf air.

In ordef to throw as much light as I pofll- bly can' on the fiibjedt which I have under- take to difcufs, viz. whether it be probable that I have borrowed any of my experiments

of Dr. H s, it may be ufeful to confider

whether his doftrine concerning air, contain- ed in his Syllabus, lately publillied, be fuch as may be fuppofed either toh^vt fuggefied, or to have refitlted from thofe experiments. If our conclufions be totally repugnant, it will hardly be thought probable that our premifes were the fame. Now that our conclufions are totally repugnant, will be evident to any per- fon who fhall infped his Syllabus and my fe- eond volume ; and it is fomething remarkable that our opinions are, in no refpeft, lb much the reverfe of each other, as in what relates to that very fpecies of air, the difcovery of which, the evidence of Dr. Brocklefby (if it could have determined any thing at all) would have given to Dr. H— - — s.

It

Philofophical Empiricifm. 53

It was exceedingly fortunate for me, that Dr. H s happened to publifh this Sylla- bus of his, at this very fealbnable time; as, without it, my defence could not have been fo complete as I am now able to make it ; fo that, without having ever thought of the mat- ter, I find myfelf pofTefTed of the earneft wifii of Job, My adverfary has written a Book. For now, out of his own mouth I can con- vift him i and fo long as there remains a fingle copy of that precious Syllabus^ I mud Hand acquitted, and he condemned.

In this fedtion I propofe not only to point out

the efTential difference between Dr. H s's

opinons and mine, but, that my reader may derive fom^ little advantage from the difpute, I fhall, as I have done in the preceding fec- tions, at the fame time, (hew how exceeding- ly frivolous are his objections to my do6lrine, and how very crude, futile, and contrary to fa6t are his own ; not forbearing to laugh where we mufi ; fmce there is, in truth, very little room for candour.

In this curious fyllabus, Dr. H s re- peatedly calls add ah\ alkaline air, and ??itrous air, p. 21, 27, conceits; alluding, no doubr» to myfelf, who lirft adopted thele terms. Now E 3 £^^J5

'§4 Philofophical Empiricifm.

this mnft have arifen from his ignorance of the nature and ufe of words^ as if any perfon was not at liberty, (like Capt. Cook, or any Other navigator) to call a thing which had no name before, by vv^hatever name he pleafed,-, pr as if the nature of the thing was affected by the choice of a term. If inftead of air^ I had ufed the word emanation^ vapour, principle, or Dr. H- — r-s's more favorite term elenienty would there have been any real difference in the fubftance, fo differently called? or, by call- ing them air, are the falls that I have difcQ- vered relating to them the lefs true.

Befides, Dr. H~s himfelf ufes the term inflammable air, without the leaft fcruple, though, according to his theory, there is not a particle of ajr in that fluid. For he fays, after me, p. 43, " that it confifts entirely of acid and phlogifton." This was my own con- clufion from the experiments mentioned in my lirfl volpmej but I have now rejeded that opinion, becaufe I have fince that time pro- cured inflammable air from metals by heat only, without employing any acid whatever.

Dr. H s, however, is very welcome to

keep my old opinion, if he prefers it to my new one. But which foevcr of the opinions Jie adopts, he is certainly obliged to me for it.

Not-

Phihfophical Empiricifin. 55

Notwithftanding Dr. H s thinks proper

to call nitrous air, acid air, and alkaline air, mere conceits, and to confider almoft all my originality as a mere hiack to make plain things myfterious-and cbfcure, I cannot help thinking that if the conceits had been his own, and if he himfeif had had as good a knack at. thefe things as I have, he would have thought the conceits to be very pretty ones, and would have been not a little proud of his knack of ftriking them out. And it is poffible, that if he had produced any fuch conceits of his own, he would not have looked with fuch envious eyes on ihofe of others. On this account I really wilh that he may have better fortune in his inquiries ; for then, while he is exulting in hiso\vnd]{covevics,?ind making moun- tains of mole- hills, other quiet people may hope to enjoy their own property unmolefted by him ; unlefs he Ihould refemble the lion in the fable, who, though he had no hand in catching the flag, challenged all the four quarters of it for himfeif.

I have obferved that Dr. H s has done

me the honour to adopt feveral things from my firft volume, but I fee nothing common to us both of what is contained in my fecond vo- UlPic, except the mention of vitriolic, and E 4 acetous

^S Philofophical Empiridfm.

acetous dr^ which terms he heard me make life of, and which he calls conceits, and an intimation that he can explain the pheno^ menon of detonatvm without fuppofmg a de- ftruflion of the acid. This was an eafy and neceffary refult from fome of my new expe- nments, efpecially thofe that relate to dephlo- gifticated air, in the difcovery of which he certainly had nothing to do.

His whole philofophical theory refts upon the foundation of there being diftind pri- mary elements of matt-rr, of which he makes feven, viz. earth, ivatcr, alkali, acid, air, phh- gijlon, and light. All thefe, he afTerts, p. g^ to be impenetrable, im-mutable^ and inconvertible. But nothing can be more uncertain, or ha- zardous, than fuch a pofition as this. We are far from being fufficiently advanced in the knowledge of nature to pronounce concerning its primary conftituent parts.

Dr. H— - — s more efpecially afTerts, p. 17,

that the pretended coiiverfion of water into (arth is an erroneous notion. But while he pre- tends to have confidcred the experiments of Boyle, Borrichius, \Va,llerius, Leidenfrofl, Margraaft, Eller, and Lavoiiier (which is caiculated to convey an idea of his extenfive j-eading) he has overlooked the more deeifive

Thilofophical Empirkifm. 57

experiments of his countryman, the ingenions Mr. Godfrey, who converted the whole mafs of a confiderable quantity of diftilled water into a perfectly dry earth. For my own part, I fee no reafon to doubt of the faft ; and what is much more, Mr. Woulfe, who is unquef- tionably one of the ableft and moll judi- cious chemifts of the age, fays that he has ieen enough, in his own experiments, to make him perfectly fatisfied with refpe(5l to it.

Dr. H ' — s calls earth an inconvertible

element, but I will undertake to convert the whole of a quantity of earth into what he fhali be obliged to call air ; and, provided it be pure earth, by which I mean free from phlo- giiton, it fhali be relpirable air.

He fays, p. 44, that " the nitrous acid ** prevents the formation of inflammable air, ** in all circumftances yetdilcovered;'' whereas, if he had read my firft volume with care, 'l^e would have found that, by a very eafy pro- cefs, I can always make inflammable air from the nitrous acid, viz. by putting iron, or liver cf fulphur into nitrous air,

To mention a few other articles in this cu- rious fyllabus that do not relate to air, but foni£ other gf his dements : he fays, p. 46,

§9 Philofophical Empiricifm.

50, 51, that "fire confifts of light and phlor " gifton, and is not a certain motion of mat- " ter ^ thzit blaze" (I fuppofe he n\t2in^ Jiame) " is a mixture of fire and a phlogiftic matter, " which has not formed fire, p. 54; that light " is not" (what Newton fuppofes) " a mat- " ter fent forth by the fun, or ftars, or pla- " nets, p. 6s ; that darknefs is not the ah- *' fence of light, or any privation of light, ib. -y ** that illumination, commonly called light, ** and darknefs, are with refped; to light, *'^ what found and llillnefs are with refpeft to *^ air, p. 66 ; that our fenfe of colour is our *' perception of the modifications of the vi- -" brating motions of light, and that the {tvtp, " prifmatic colours are, with refpedl to lights " what the {oxtn tones are with refped: to air, " p. 72 ; that fpecific gravity and denfity are " not commutable terms ; that there is not '^ neceffarily more matter in a cubic inch of " glafs, than in a cubic inch of rozin, for "^ that gravity depends as much upon the fpe- " cies of the gravitating matters as upon the " quantity of them, p. 48 ; that phlogifton *^ does not gravitate, and that it has a power "^ whereby it counterafts the gravitation of *^ other matters, p. 47."

Theie

Philofophical Empiricifm,, 59

Thefe and fuchlike long-exploded, and crude notions (fo many of which I believe were never thrown together into the iame compafs fince the age of Ariftole or Cartefuis) are delivered in a manner and phrafe fo quaint, and a tone fo folemn and authoritative, as gives me an idea that I cannot exprefs otherwife than by ^he term Philofophical Empiricifm,

SECTION

6o Phlkfophkal Empirlcifml

SECTION ^

Miscellaneous Observations."

I Hiall begin this fedbion with fon^ general

obiervations on the nature of the accufation brought againfl: me, and of the evidence by which it is fupported.

My acquaintance with Dr. H s com-*

menced on the 6th of February 1775 ; and he, lays (for I happen not to have any note of that memorable sra myfelf) that it had been dif- continued nine months, on the 3d of Decem- ber following. It muft, therefore, have ter- Ttiinated in the beginning of March. But I believe he is miftaken about two months, and that it was in the beginning of May ; fo that I eive him two months more than he claims. Three months, then (a great part of which I fpent in the country) my acquaintance with Dr. H- s lafted.

The fecond edition of my Treatife on air had been publiflied feme time before I had fo much as heard the name of this gentleman, to whom ii has been faid, and with very great confi- dence, that I owe all my difcoveries ; fo that he

can

Phtlofophical Empiricifml 6i

'can have no claim to any thing mentioned in that volume. At the fame time, alfo, it is well known to my friends, and I mentioned it to

Dr. H- s himfelf, the firfl time I law him,

that I -had materials for z fecond publication on the fubjeft. I muft, therefore, at that time, have had tlie materials iov xht hulk of the fe- cond volume, I luppofe about three fourths of it. The -remaining fourth part, therefore, is all that can lie open to his claims ; and even with refped; to this, he will find that I am able to produce evidence, that every courfe of ex- periments, of any confequence, was begun, and pretty far advanced, before 1 knew him; io that I had little to do befides merely coni^ pkting them, excepting what relates to the ve- getable acid air, which is a thing of very little value, and the experiments on the fluor acid, which Dr. Brocklefby, the only evidence that has yet appeared againft me, does not pretend to have feen with Dr. H -s.

In fa(El, therefore, there remains nothing of any value for him to lay his hands upon, ex- cept the completion of the difcovery concern- ing dephlogijiicated air, which I had begun be- fore I knew him; and though his friend has afferted, in general, that he favv ^// the experi- ments I Ihewed him (and thefe were among

them) with Dr. H -s, the circumftances of

that

62 Philofophical Empiricifm,

that fa6b have been ftated to be fiich, that t am fatisfied my reader mull be fomething more than prejudiced, to imagine that it was even poflible he Ihould hat^e feen them*

When I firft mentioned the fads to Dh

H s, he even pofitively denied that any

air could be got from the fubftance from which I aftually procured that fpecific kind of air ; and the neceffary conchfions from thefe experiments are not only not found in his printed Syllabus^ but are the very reverfe of the fundamental dodrines of that fyllabus.

Now I will venture to fay that whenever any , other article is examined, his claim to it will appear to be equally unreafonable and abfurd* The book, however, will foon be before the public, and he may then call his rapacious eye over every paragraph of it ; and let him diftinguilh his property there, if he can.

I am very confident, that if the dates an- nexed to any of the articles were concealed, and he was required to name his own, he would jull as foon take what was done before I knew him, as what was done after that time. In fad, he has an equal right to all^ or none.

it

Phmfophical Empricifm. 6^

It feems, however, very extraordinary to me, that he fliould, at the fame time, defpife all that I have done, calling my difcoveries mere conceits, and fay that I am pofTcfled of no- thing but a knack of rendering what was intel- ligible before^ myjlerious and obfcure^ and yet co- vet thofe things for himfelf. The iccond vo- lume, I can aiTure him, contains nothing buc more conceits^ of the fame kind v;ith thofe m the firfl:, and nothing is exhibited in it but the exercife oi the fame knacky whether of dark- ening or enlightening things, that was dil- played in the former volume.

According to Dr. H — — s's account of the ufe that I have made of the difcoveries of chemifts, neither himfelf, nor any other per- fon, has been really injured by me; for I have only difgraced myfelf. What reafon, then, can he have to complain ? Let him on- ly publifh his experiments, which are fo very intelligible ; and if it appear, by comparifon, that mine are only calculated to throv/ dark- nefs upon his light, their credit cannot lall long; and every thing that 1 have done, con- tained in both my volumes, muft vaniih before his publication, like Satan, the prince of darknefs, at the touch of Ithuricl's fpear. if all that I have done be what he reprefents it, a mere impofttion upon the public, v/hy cannot

he

^4 Philofophicdl Empifidfiiu

he be content that I fliould have all the infa- my of it to myfelf. Is it that he is willing, out of a principle of compafiion, to (hare the burden with me ?

As he fays that / have treated others as t have treated him, I think I may fafely con^ elude, that I have only treated him, as I have treated others ; and therefore that I have flolen no more from him, than I have done from others. Now, as my works are open to the public, let him fhew what it is that I have taken from others, without acknovvlegementi But as 1 am confident that all the world will acquit me of any thing like plagiarifm with refpecc to them, they will as readily acquit me of the fame charge with refpect to him.

During my acquaintance with Dr. H-- — Sj he was perpetually talking of his difcoveries in general, but without diftindly fpecifying them % fo that 1 do not retain a fmgle idea of any that he has ever made, and I hav.: never heard the lead mention of any of thern except from himfelf*. Indeed the great burden of his dif^ courfe with me was, that people came perpe* ' tually teizing him with queilions, took up

* I mull except a fmgle circuaifiance, racntioned in a iate volume of the Philo/ophical Trai3jayiious.

2 hk

Philofophical Ewpiricifm. 65

his time, got hints of difcoveries from him, and then piibllfhed them without making any acknowledgement. But I remember that he never mentioned the name of any of thofe perfons. 1 now publicly call upon him to name them, that we may know one another, and compa;re notes ; for 1 fancy we fhall all find ourfelves in the fame fituation, that there has been much cry and little wool ; that thefe many perfons, all publifhers of experiments, have written from their ov/n funds, and than we fhould have had a very fcanty fupply, if

we had only had Dr. H s's hints, and

voluntary communications, to depend upon.

Chemiftry, hov/ever, being a wide field, and myfelf having had accefs only to a one fruitful corner of it, I, in the great fimpli- city of my heart, entertained no doubt, but that while I was exploring one place, he was doing the fame, and with the fame fuccefs in another -, and there was certainly room enough for us all. But I now begin to fufpe6l that (whether through his too great eagernefs to catch at every thing, and fecure the whole field to himfelf, or through fome other caufe) not having had the good fortune, in faft, to lay hold of any thing himfelf, he has been feized with a longing defire to fnatch a few of F the

€6 Philofophical Empiricifm.

the flowers that I and others had been very quietly gathering; thinking that, out of fo great a number, he might, without fear of de- tedion, fecure a few: and could he have con- tented himfelf with enjoying his pretenfions with more privacy and difcretion, he might have fucceeded better.

Now could we all^ on whom he has been making his depredations, only know one of another, though we fhould only be half a do- zen of us (and yet, from his own account, which pretty much refembled that of FalitafF, I fhould think that we cannot be lefs than a /core) we might perhaps, by confulting to- gether, hit upon fome method of fatisfying this unfortunate experimenter. We might each of us agree to make him a volunta- rily contributioa out of our common flock. For my own part, I love my reft and peace fo much, that rather than have fuch another affair as this, I would freely furrender to him one or two leaves of my Regijfer, and a few good hints to work upon into the bargain.

Dr. H s feems to be much offended at

the rapidity^ as he calls it, of my philofophical publications. Now every man has a peculiar manner^ and a peculiar/^/*?. No two men are,.

in

Phllofophkal Empiricijhi, Cy

in all refpefls, alike. He is not what I am, nor am I what he is. It may be my fate to be a kind o{ comet, or ?L^m\n^ meteor in fcience, in the re- gions of which (like enough to a meteor) I made my appearance very lately, and very un- cxpedledly ; and therefore, like a meteor, it may be my deftiny to move very fWifcly, burn away with great heat and violence, and become as fuddenly extinfl. Let Dr. H s, there- fore, if he be wife, keep out of my way ; let him wait till my faced period arrive (which, in the nature of things^ cannot be far diftant) and he may then, after feeing my fall, like a Oow fober-moving />/^;zi?/, attended by his faith- ful fatellite Dr. Brocklefby. perform his own revolution unmolefted, when I Ihall be in- volved in darknefs.

As a circumftance that will have fome weight with our judges, who are to decide whether it be more probable that the difcoveries in quefti- on be mine, or Dr. H— — s*s, I think he fhould be required to produce before them any dif- coveries concerning air, that are unqnefiionably his Own, as a fpecimen of his abilities in this way 1 or, at leaft, difcoveries of fome kind or other. Thus, when the wafps claimed the combs and the honey of the bees, they were required by their equitable judge, in iEfop, to produce fuch combs themfelves.

F 2 I Ihail

68 Philofophical Empiricifm,

I fhall now conclude this appeal to the pub- lic with a letter to my accufer, and another to his witnefs ; after which I fhall fubmit the de- cifion of my caufe to a jury of our peers, the fublic j acknowledging, whether Lord Mans- field will agree with me in this, or not, that they are competent judges both of the law^ and of \.hs.fa5i.

To Dr. H— -s.

Sir,

It is fomething odd that the fubjeft of the only paragraph in my letter which you thought required an anfwer, is the only one which it is impoflible for me to make a reply to in yours. For, indeed, as you fay, our notions of honour differ fo very widely, that it would be going too far back, for a correfpondence by letter, to come at any common principles on which we might argue. Befides, the public may have notions of honour different from us both, and they will judge between us. To which of pur maxims they will moft incline, time will dif- cover.

You fay that, " if any other gentleman had " propofed to you the queftion that I did, an

" anfwer

Philofophical Empiricifm. 6g

*' anfwer would have been neceffary." Now, as I cannot pretend td be any other perfon now than I was then^ I imagine you will flill think aji anfwer to me, unnecejfary ; but as with refpeft to tht public, or to yourfelf, you may, poflibly, think it expedient, and your time may be too much taken up in the profecution of yourim- menfely valuable difcoveries, even to read the whole of this pamphlet, I fhall, in a few diftindt paragraphs, recite all that it particularly con- cerns you to reply to.

I. You muft diftinftly recite thofe difco- veries of yours, which you cTiarge me as hav- ing publifhed as my own -, proving that you had publifhed them before me, and that I knew of your having made them at the time of my publication. You fay that "If you fhould an- " fwer my queftion, you would commence it " with comparifons of the dates of my rapid *' publications, with the dates of your courfes " of chemiflry." Nov«7 this is more than ne- cefTary, unlefs you can prove that I knew any thing of you, or of your courfes, before the 6th of February laft, and can find in the two firfi leSfures of the courfe, which you began on that day, the feeds of my difcoveries fubfe- quent to that date.

But

f6. FUhfophical Empincifin,

But I find, by your friend Dr. Brocklefby, that your very firji courfe began in June 1774-, whereas my firft volume on air was ipublilhed feme months before that date; fo that, the' your voice could have been heard from your laboratory in Greek-ftreet, Soho, London, to my fire-fide at Calne, in Wilt- fhire, I could not have profited by your in- jftruflions. My unfortunate conceits were then ^11 abroad, and, to my everlafting fhame, were at that time well known to philofophers in many different parts of Europe ; and long before that time, the Council of the Royal Society, wanting the wifdom of your advice, had been fo infatuated, as to have conferred upon me their annual prize-medal for about one half of thofe that are contained in that iirft volume. Milled by their ill-founded ap- plaufe, I have gone blindly on in the fame walk, till my conceits are now more than four times as many as they were at the time of my firfl publication.

2. After you h^vt made good yomjirjl charge of plagiarifm, with re^ed to yourfelf, pkafe to prove your fecond alfo, viz, my plagiarifnj "with refpecfl to otberi.

3, That

Philofophical Empiricifm, 71

3. That this altercation of ours may be of fome life to the public, and to make it worth their while to give us a hearing, 1 wifh you would difcufs the feveral topics on which your philofophical notions and mine differ. It is to be wifhed, more efpecially, that you would prove your favourite dodrine, that fixed air confifts of common air and phlogifton j that acid air, alkaline air, and nitrous air, &c. &c. &c. are mere conceits; and that your funda- mental principle of the abfolute inconvertibi- lity of what you call elements into each other, is well founded, efpecially that earth is not convertible into air, as I aflert, and you deny.

4. It would be particularly edifying to the public, if you would favour them with an elucidation of your extraordinary Syllabus, a few things in which I took the liberty to point out, d.^ wanting fome illujiration \ as your no- tions concerning/r^, light, phlogifion, &c. But perhaps you may, in your great prudence and difcrction, tliink: it quite fufEcient, if, for the prefent, you can give fatisfadlion to your pupils with refpedt to them : and I own, upon refledion, it would be unreafonable to require of any perfon of your defcription, that he fhould publifh to the world all the fecrets of his Art.

F 4 ■ .5' As

72 Phikfophicd Empridfm,

. 5. As to the particulars which only pafled in converfdtion between our" two felves, and which have not yet been communicated to the public, not even in your amazingly-compre- henfive fyllabus, as concerning the fedative acid^ air that has too little ■phlogijlon^ &c. &c. &c. it no way concerns the public ; but perr- haps you may chufe, while your hand is in, to clear up thofe matters as well as the reft.

6. Above all things I muft infift upon it, that you fpecity the na'mes of the many perfon$ who have behaved towards you with the fame bafenefs and ingratitude that I have done ;

•that the public may judge of the credibility of your charge againft me, by comparing it with your charge againft others, probably much more refpeflabie perfons than my- felf.

7. As to your perfonal behaviour to me, and your reafons for it, you may give juft v/hat account you pleafe. As my chara6ter is pretty well known, thofe who are acquaint- ed with me will judge whether your account be probable or. not j and though I do not pretend but that my memory may fail me with refpe6t to fome circumftayices of things, \ think a man will hazard too much who

Ihali

PhiJofophkal Empmdfm. 73

ihall charge me with any wilful mifreprefen- tation of a faft. I would not for the fake of all the reputation that a man can get by phi- lofophy, or by writing, have the feehngs of that man who fhall charge me with having told a deliberate falfehood ; for if he have any knowledge of me, he muft, at the fame time, be confcious of telling one himfelf ; afTerting what he does not believe.

I am, Sir,

Your humble Servant, Shelburne-houfe, 8 Dec. 1775. J. PRiESTLEy.

P. S. As I have now the honour of intro- ducing you to the Public, as Dr. Brocklefby introduced me to you, I hope you will not immediately adopt the ftyle of your letter to me, with which our intercourfe terminated, but rather that which you firft ufed to me, as expreffive of that deference and refped which you thought due to a new acquaintance.

If in any part of this pamphlet, or letter, I have inadvertently offended you, I fhall hope to be favoured with a remonftra^ice on the fub- jeft. The title^ at leafl, cannot difpleafe you. In this I have not been partial to myfelf ; for

whenever

74 Fhihfophical Empricifm,

whenever the publication is mentioned, it will be called my Philofophical Empricifm^ and not yours. Your friends, therefore, may be ex- pedled to circulate it as well as mine.

To Dr. Brocklesby,

Dear Sir,

I am forry to obferve that, in your lafl let- ter, you drop the ufual ftile of ftiendfhip, in your addrefs to me j but this Ihall not make me difcontinue it with refpe<5t to you. For though, by means of your indifcretion, I have long lain under a great load of odium, and you have occafioned me a great deal of trouble in confequence of it, I believe it was very far from being your intention to injure me : and whatever I may think of you as z philofophery or as a writer^ I Ihall always refpeft you as a gentleman. Befides, your known attachment to the caufe of Liberty, would alone, if you had nothing elfe to recommend you to me, difi arm, in a great meafure, my refentment.

I have no obje(ftion even to your enter- taining whatever regard you pleafe for your

friend Dr. H s, who, how deep

foever he may be 'in philojophy^ and how laappy a talent foever he may polTefs of com- municating

Phihfopbical Empiricifm, 7^

munlcating his own clear ideas to others, (of which yourfelf, who have fo long been his pupil, have exhibited the moll fatisfafto- ry proof) certainly has not, in return, re- ceived from you ail the accomplifliments of a gentleman -, being manifeftly deficient in the firft rudiments of that charader, viz. good manners, as his behaviour, and his letter to me, will teftify,

I would obferve, however, that feveral parts of your letter might very juftly give me of- fence, efpecially your intimating that by pro- pofing my queftions 1 meant not to dear up the fuhje^ (though nothing could be better calculated to anfwer the purpofe, as the iffue has proved) but either to puzzle you, or lead to farther perplexities. For they could not have puzzled or perplexed any man who was a competent evidence in the cafe.

AH the particulars of your letter that are true (for feveral of the articles are notorioufly falfe) are either things that have been long known to all philofophers, or are contained in my firft volume ; and yet, after reciting them, you bid me " afk myfelf whether any •* thing that I fhewed you at Shelburne-houfe ** could appear novel to youj fince my giving

" new

']^ Phikfophical Empiricifm.

"„ .new names to v^hat you had feen before^ *^ could i}oti conftitLite any new difcovery.'* !^fow I lliewed you feverai very remarkable ex- periments, of which nothing is fo much a? hinted at in your letter ; and therefore, or^ your own teftirriony, they muft have been quite new to you, whether you were aware of it or not.

You complain that you have been drawn by me into a difpute againft your will ; but, Dear Sir, is it not rather you who have drawn me into this difpute? And I do aiTure you it is. much againft my will. A very ferious accu- fation has been brought againft me, refpedling, not, as you reprefent it, the exclujive right to a philofophical difcovery^ but affecting rny cha- raSier as an honeji man, and you are the only perfon who have ftood forth in fupport of this accufation. Can you then ferioufly blame me for calling you to prove what you acknow- ledge you have afferted, and for propofing fuch queftions as were evidently neceffary to afcertain the validity of your teftimony ? A moment's refleftion will convince you that, in juftice to myfelf, I could not have done other- wife.

You

Philofophical Empiricifm, j'j

You muft now. Sir, give me leave, in re- turn for your anecdote concerning Sir Ifaac Newton (which you have intireiy mifapplied in my cafe) to tell you a ftory which you can- not mifapply, and I hope it will not be loft upon you on a future occafion.

A Chinefe Mandarine had procured an Eu- ropean refleding telefcope, and a friend of his, wifhing to have another exactly like it, put it into the hands of a Chinefe workman, who was famous (as many of the Chinefe are known to be) for the imitation of any thing he faw. Accordingly, having got the inftru- ment into his hands, he furveyed it with great attention, took it to pieces, and carefully meafured the dimenfions of every part. He then made a tube of 'the very fame fize, and mounted and poliihed it, fo as not to be dif- tinguifhed from the other ; and with refped to the infide of it, he put pieces of polifhed me- tal, and pieces of tranfparent glafs in their proper places, and precifely at their proper diftances from each other j but without at- tending to any more exaft curvatures of their fuperficies than his eye, which was a very good one, could diflinguifli : and then concluded that he had completely conftruded the telef- cope. And certainly a Chinefe Dr. Brock-

kfov

^8 Philofophicd Empiriciftn*

le(by would have faid that they appeared to he nearly the fame ; and yet the European inftru^^ ment would magnify remote objeds with great diftinflnefs, whereas, through the Chinefe te- lefcope, nothing could be feen at all.

Now this I take to have been the difference

between Dr. H^ s*s experiments and mine,

and I hope that the next time that you (hall fee a man Handing by a tub of water, or a bafon of quickfilver, with jars and phials, &c. before him, filled partly with air and partly with water, with a lighted candle, and a variety of little implements at hand, and transferring his different kinds of airs, with Ibme degree of dexterity, from one veiTel to another, a red colour appearing here, and a white one there, you will not be fo ready to affirm that the ope- rator was inftituting the very fame experiments that you faw at Shelburne-houfe*

As a ftory frequently begets its own like- nefs, and examples of this kind may be ufefui to you in the way of apology, as well as of admonition, I fhall, while I am in the vein for it, tell you another.

Your exprefling no fort oi furprize at fee- ing my new experiments, reminds me of the

in-

Philofophical Empiridfrn. 79

indifference with which Tobiah, a very fenfi- ble native of Otaheite (fo that it is no difpa- ragennent to you to be compared to him) faw a horfe for the firft time at Batavia, when it •was imagined that he would have been ftruck with the greateft admiration, efpecially as he was remarkable for his curiofity, and his at- tention to every thing that appeared new to him. But when he was afked by Mr. Banks, who told me the ftory, if he did not admire that noble animal ? he faid, " No, for there " was nothing extraordinary in it, except its, *' fize, as fuch animals were common enough *' in his own country." Upon inquiry it ap- peared that he took the horfe to be nothing more than a large dog.

Unfortunately, this Otahcitian Dr Brock- lefby did not live to return to his own coun- try. But fuppofing him to have returned, and his countrymen gathered about him, afkirtg him whether he had feen any thing new in his travels ; he would have faid, " No, thefe peo- " pie (who are faid to be philofophers high in " modern rank) with great trouble and ex- ** pence, run over the world, on purpofe to *' make what they call difcoveries, and I fup- *' pofe there are people on whom they can im- *' pofe. But as far as I fee, and I have been

" long

8o Phikfophical Empiridfm.

" long enough with them to judge, they only *' amufe themfelves, and the world, with giv- " ing new names to things that we all know as " well as they do. They pretended to fhew " me a moil extraordinary animal, and thought " to have furprized me exceedingly v/ith the *' fight of it; but though they called it by a " name that I had never heard before, and *' that I cannot now recoiled:, you may depend *' upon it, it was nothing more than a dog, *' only a little larger than our dogs generally '* are. It had only four legs like ours, one " head, one tail, and a couple of ears, and it *' feemed to run at the fame fpeed. As for the " fpecies of the animal, let them pretend what " they will, be affured by me it. was. the very " fame."

I hope, Dear Sir, you will not think the worfe of me for endeavouring to give a turn of pleafantry to an affair that, fome time ago, wore a pretty ferious afped. Believe me, I re- tain no animofity againft you. I have even no objeflion to feeing or converfing with you as ufual. Only I fancy it will be equally agree- able to us both to fay nothing, for the future,

about philofophy^ or Dr. H s, but rather

4 to

Philofophical Empiricifm. 8i

to talk about America, and our common friend Dr. Franklin.

I am, Dear Sir,

Your very humble Servant^ Slielburne-houfe, Dec. 9, 1775. J. Priestley.

P. S. Had you liftdied to the gentle and timely admonition of Dr. Hunter, at the time of your making the declaration abovemen-

tioned, viz. " I fuppofe that what Dn H s

*' Ihewed might be fomething like thefe experi- " ments, but they might notwithftanding, in " reality, be very different from them," it would have been happy for me, and perhaps alfo for yourfelf, and even for your friend Dr.

H s, in whole reputation you fo warmly

intereft yourfelf.

0 THE

Phikfophkal Empiricifm,

THE CONCLUSION.

I have now made the befl defence that I can to the general and indijlin^i charge that has been brought againft me, and am waiting (with how much anxifty may well be ima- gined) for the particulars of my accufation, of the nature of which I am juft as ignorant as my reader himfelf. I take it for granted, however, that it relates to fome of the arti- cles contained in Dr. H s's fyllabus,

which was intended, no doubt, to comprife the refult of all his difcoveries, thofe that I have been pilfering, as well as the reft; and indeed it takes in the whole compafs of philo- fophical knowledge. But then, among fuch an immenfe number of difcoveries, great and fmall, how can I determine which of them it is on which he v/iil found his charge.

I believe 1 muft, in this cafe, have recourfe to the method formerly ufed in taking the

fortes Virgilian^ y and, as it is poffible, though

not through a deficie?tcy^ yet through a redun-

4 dancj

Philofophical Empiridfm. 83

dancy of his articles of accufation (which is no 1 f=> eiTibarrafling; Dr. H- s himfclf may- be as much at a lols as I am, I would recom- mend the fame method to him -, and if he Ihpuld not happen to know what it is (as the procefs IS not a ftriflly chemical one) I will teil him, that he has nothing to do but to open thf book at random, and the firft para- graph that he ihall cafually call his eye upon, is the article wanted.-

I am not lawyer enough to know whether it would avail me at all in this cafe, to turn informer againft my profecutor, or I could prove that not a fingle article mentioned m Dr. Brockicfby's elaborate letter (which I doubt not contains a full and accurate account of all the recondite doflrines, and profound dif- coveries, delivered in the Greek-ftreet lec- ture) whether true or falfe (for the account confifts of a due mixture of both) belongs to Dr. H s.

If this will not avail me, and my defence, after all, be deemed unfatisfaftory, I fhall be anxious to know to what punijhment 1 fhall be fentenced. For if my crime fhould be ad- judged to be any thing more than petty larceny^ I am apprehenfive that, as we have no co- . G 2 lonies

84 Philofophical Empricifm.

Ipnies for the convenience of tranfporting fe- lons now, I fhail inevitably be dejiined to the cord.

I do not know whether my nativity was ever regularly caji-, but if it was, I am con- fident it muft have appeared, that I was born under the malignant influence of feme or other "of the planets, to which the old chemifts paid a more particular devotion ; and it is well known that they had much recourfe to the planets. For 1 cannot otherwife account for my being fo exceedingly obnoxious to lecturers in cheniijiry as I have been. If I might adopt thedoclrinesof my Scotch antagonifts, I Ihould fay they feem to be pofleiTed of an injiin^ive antipathy towar-ds me, and to fall upon me as naturally as the wild affes, in Arabia, fall upon the horfe, or, if they like it better, as the wild horles of Arabia fall upon the afs.

For, a few years ago, - I happened to be but a quarter of an hour in company with another celebrated le(5lurer in this branch of liberal fcience, in this metropolis, and I narrowly efcaped being brought into a fcrape as

b^d as this that I am now in v/ith Dr. H s.

It

Philofophical Empiricifm. J? 5

It was, indeed, much of the fame nature, and, as "far as I can forefee, would have ended as this is likely to do. Nay it looked much more formidable at its outfet. For I was informed not only that I had publilhed dif- coveries communicated to me in that unlucky quarter of an hour, without any acknow- ledgement, but a publication was threatened of all my plagiarifms, which, as I was then but young in this bufinefs (and not cafe- hardned, as I now am by all kinds of abufe) would certainly have overwhelmed me. And the learned ledturer (though I believe he never

acted in concert with Dr. H s) exprefTed

even greater contempt of my experiments

than Dr. H s has done, and in a ftile

equally corred and elegant.

When, however, the fad was inquired into, it only appeared, that I had not given to an excellent philpfopher, with whom I am now better acquainted, an experiment, which, as the chemift defcribed it, was not fa^, and which, as it ought to have been defcribed, I had not claimed to myfelf, but had given to another perfon, who had adtually made the experiment, and had publifhed an account of it long before.

Having

S6 jPhilofophical Empiricifm,

Having related the particulars of my own condudt, and my own experiments, as far as the purpofe of my defence requires.

'Sua narret Ulyjfes.

Ovid.

FINIS.

ERRATA.

Page 6. 1.4. (from the bottom) £or none, K^id none of them >

P. 4. 1. II. iov fubJlancBy xtzdfubjiances.

P. 58. 1. 5. for not, read not yet.

P. 59. 1. 4, for Arijiole, read Arijlotk^

A Cata-

A Catalogue of BOOKS written by JOSEPH PRIESTLEY, LL. D. F. R. S.

AND PRINTED FOR

J. JOHNSON, Bookfeller, at No. 72, St Paul's Church- Yard, London.

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10. Aa

BOOKS tvtiften hyPr. PRIESTLRY.

10. An Examination of Dr. Reid's Inquiry into the Human Mind on the Principles of Common Senfe, Dr. Beattie's EfTay on the Nature and Immutability of Truth, and Dr. Oswald's Appeal to Common Senfe in Behalf of Religion, the fecond Edition, 5s. fewed.

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31. Considerations for the Use of Young Men, and the Parents of Young Men, 2d.

Jlfo,

Alfo, puhUJhed under the BireSiion of Dr. Prieftleyj

THE THEOLOGICAL REPOSITORY;

Confining of original Effays, Hints, Queries, &c. cal- culated to promote religious Knowledge, in 3 Vo- lumes, 8vo. Price 18s. in Boards.

Among other Articles, too many to be enumerated iu an Advertifement, thefe three Volumes will be found to contain fuch original and truly valuable Obfervations on the Doftrine of the Atonement, the Pre ekijience of Chrtjiy and the Infpiration of the Scriptures, more efpecially re- fpe^ling the Harmony of the Evangelijis, and the Reafon- ingof the Apollle Paul, as cannot fail to recommend them to thofe Perfons, who wifh to make a truly UtQ En- quiry into thefe important Subjefls.

In the Firft Volume, which is now reprinted, feveral Articles are added, particularly Two Letters from Dr. Thomas Shaw to Dr. Benson, relating to the Pallage of the Ifraelites through the Red Sea.

1775.

On the ^oib of December will he publifhed.

Price Six Shillings in board?. The SECOND VOLUME of

Experiments and Observations on different Kinds of AIR.

With an Alphabetical Index to both the Volumes, By JOSEPH PRIESTLEY, LL.D. F.R.S.

mfsjBDf.

Hi

BOOKS nuritan by Dr. PRIESTLEY.

through the Red Sea. Among other Articles, too many to be enumerated in an Advertifement, thefe three Volumes will be found to contain fuch original aud truly valuable Obfervations on theDoftrine of Atonement, the Pre-exiftence of Chrijl, and the Jttfpiration of the Scriptures more efpecially refpefting the Harmony efthe Evangelijist and the Reafoning of the Apoftle Paul, as Cannot fail to recommend them to thofe Perfons who wifh to make a truly free Inquiry into thefe important Subjedls.

THE END.

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