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


With various Obfervatioms relating td 


Vivitur ex rapto. Non hofpes ab hofpite tutU3. 



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

' ADAMS W.i 

/f- J ■:;» 


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 


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 

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. 




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


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 


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 


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 


* 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 

^ 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, 


'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. 


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- 

Philofophical Empiricifm, '*} 

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

I am, Sir, 

Your very hurnble fervant 
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 

30 Nov. 1775. Richard, Brocklesby, 

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- 


10 Philofophical Empiricifm. 

cept when a gentleman has inadvertently ofr 

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- 

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) 


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, 

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 

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- 

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. 

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, 


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 


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 


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. 


Philofophical Empiricifm, 23 


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 


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 


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 


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 

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 


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 


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 


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 


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 


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, 


Thilcfophical Empiricifm, ^g 


^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 

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 

.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 


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. 


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 


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^ 

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 


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 


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 

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- 


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. 


Philofophkal Empiricifnu 


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. 


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. 


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." 


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, 


6o Phlkfophkal Empirlcifml 


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 


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 


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. 


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 


^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,. 


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. 


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- 

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. 


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- 

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 


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, 
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 


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- 

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- 


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- 


^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 


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^ 
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. 


Phikfophkal Empiricifm, 


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 

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 

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. 


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. 


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. 




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