Goes to Leeds as minister of the Mill Hill Chapel--Resumes his studies
in Speculative Theology--_The Theological Repository_--Becomes a
Unitarian--Priestley as a controversialist--His Theory and Practice of
Perspective--His literary characteristics--Begins his inquiries on
Pneumatic Chemistry--His invention of soda-water--Receives the Copley
Medal of the Royal Society.
Although Priestley lived in philosophic contentment with his lot at
Warrington, happy in his occupations and in the society of congenial
colleagues, the circumstances of the Academy were not fortunate. The
institution never wholly recovered from the unhappy differences between
the trustees and the first head of the Educational Staff, and in time
many of the subscribers grew lukewarm in their support. Priestley had a
remarkable power of adapting himself to his environment; he was one of
the most even-tempered of men and had a capacity for being cheerful that
would have extorted admiration even from Socrates. "But," says Miss
Aiken, "the Alma Mater of Warrington was ever a niggardly recompense of
the distinguished abilities and virtues which were enlisted in her
service." One hundred pounds a year, with a house and a few
boarders--hungry lads at £15 a year, exclusive of washing and
candles--meant little towards the _res angusta domi_. Moreover, little
Sarah Priestley had made her appearance, and the uncertain prospects
which were before that young lady, coupled with the condition of her
mother's health, which was not wholly satisfactory at Warrington, led
him to contemplate the expediency of giving up school-mastering and of
resuming his profession of the ministry. Accordingly he was induced to
accept an invitation to take charge of the congregation of Mill Hill
Chapel, at Leeds, where he was already pretty well known, and thither he
removed in 1767.[12]
Although it was no part of his duty to preach when at Warrington, he had
from choice continued the practice, and wishing to maintain the
character of a Dissenting minister, he had, as we have already seen,
been ordained whilst there. His tendency to stammer was still a
difficulty. Indeed, whilst at Nantwich it was so marked that he had
almost resolved to abandon the calling. By reading aloud and very slowly
every day, and by taking pains, he in some measure got the better of his
defect, but he never wholly overcame it.
At Leeds he found a liberal, friendly and harmonious congregation, to
whom his services, of which he was not sparing, were very acceptable.
There, he says, he had no unreasonable prejudices to contend with, so
that he had full scope for every kind of exertion. His activity and zeal
in the special duties of his office led him to prepare and print
catechisms for the young and to form various classes of catechumens and
to instruct them in the principles of religion. He also published
discourses on "Family Prayer," on the "Lord's Supper" and on "Church
Discipline," some of which were not altogether to the liking of members
of the Established Church. Indeed, the first of his controversial pieces
was written in answer to some angry remarks on one of these discourses
written by a clergyman in the neighbourhood.
His return to the active duties of the ministry naturally induced him to
resume the studies in Speculative Theology which had occupied him at
Needham but which had been in large measure interrupted by the business
of teaching at Nantwich and Warrington. He now published his _Institutes
of Natural and Revealed Religion_, and began the publication of _The
Theological Repository_, a collection of papers on theological
questions, contributed by himself and a number of neighbouring ministers
and others. The work eventually extended to six volumes, three of which
were printed whilst he was at Leeds.
"_The Theological Repository_," says the Rev. Charles Wicksteed,[13]
"was one of those publications which will always appear from time to
time in every body in which there is much activity and much freedom of
thought. It had, however, a very slender circulation, and was very
little read by any but theologians of the Liberal school. Indeed, it
discussed questions which were viewed with terror by many even of the
Liberal school itself, because it, in fact, purposely deserted the
beaten track of opinion and opened out those questions on which
difficulties began to be felt, or on which fresh light was wanted. It
aimed at collecting the contributions of free, independent and
thoughtful minds--_towards_ correct ultimate decisions, without
pretending itself to furnish those decisions. This is ever a position
which the bigoted violently resent, which the unlearned cannot
understand, on which even the candid and liberal often look with a
dissatisfaction not unmingled with fear, but which is,
notwithstanding, the essential preliminary of correct settled opinion
in every age of thought. It is a position often assumed by the most
contemplative and the most thoroughly honest men of the generation,
but one which is never understood until the generation which produced
and neglected it is passed. If there were not this neutral ground on
which inquiring spirits can meet, beyond the hackneyed and settled
points in which alone the many are interested, there would be an end
to thought, which in a short time would prove an end to active,
healthy, influential and tested truth."
Shortly after his removal to Leeds, Priestley avowed himself an adherent
to that school of theological opinion which its enemies associate with
the name of Fausto Sozzini; that is, he became what has been called a
_humanitarian_, or a believer in the doctrine that Jesus Christ was in
nature solely and truly a man, however highly exalted by God.
Sozzini's doctrine brought down upon its teacher the ill-will of a
Cracow mob; his house was wrecked, his books and manuscripts destroyed,
his life threatened, and he was driven from the city. Two hundred years
later the Socinian Priestley went through precisely the same experience.
Wrecking the homes, pillaging the property and injuring the persons of
heresiarchs might seem an extraordinary way of identifying oneself with
the doctrine of the gentle author of the Sermon on the Mount if history
had not made us pretty familiar with such spectacles. At Leeds, as
already stated, Priestley published the first of the series of
controversial pieces on religion and politics which ceased only with his
death. By some strange irony of fate this man, who was by nature one of
the most peaceable and peace-loving of men, singularly calm and
dispassionate, not prone to disputation or given to wrangling, acquired
the reputation of being perhaps the most cantankerous man of his time,
who delighted in tilting against established usage, and whose hand,
Ishmael-like, was against every man's. By sheer force of circumstances
he became an indefatigable pamphleteer, apparently ever ready to
vindicate the cause of civil and religious liberty, to champion the
principles and conduct of Dissenters, and to attack what he considered
the inveterate prejudices of the prevailing religion of his countrymen.
As a controversialist his methods were beyond reproach, and the arts of
casuistry were wholly foreign to his character. He was so obviously
sincere and fair-minded that he frequently overcame prejudice and
disarmed criticism by his unconscious unwritten appeal to the finer
instincts of his adversaries. He made many enemies but he won far more
friends: the enemies were for the most part men whom history willingly
lets die; the friends were of every sect, and some of them were among
the chief glories of the eighteenth century.
The following characteristic letter to his friend, Miss Aiken, is
interesting as illustrating the action of the active, eager mind which,
as its owner says, found scope for every kind of exertion at this period
of his life:--
"Leeds, _13th June 1769_.
"Dear Miss Aikin,--You will be surprised when I tell you I write this
on the behalf of _Pascal Paoli_ and the brave _Corsicans_, but it is
strictly true. Mr Turner of Wakefield, who says he reads your poems,
not with admiration, but astonishment, insists upon my writing to you
to request that a copy of your poem, called _Corsica_, may be sent to
Mr Boswell, with permission to publish it for the benefit of those
noble islanders. He is confident that it cannot fail greatly to
promote their interest, now that a subscription is open for them, by
raising a generous ardour in the cause of liberty and admiration of
their glorious struggle in its defence. Its being written _by a lady_,
he thinks, will be a circumstance very much in their favour and that
of the poem, but there is no occasion for Mr Boswell to be acquainted
with your name unless it be your own choice some time hence. I own I
entirely agree with Mr Turner in these sentiments, and therefore hope
Miss Aikin will not refuse so reasonable a request, which will, at the
same time, lay a great obligation on her friends in England and
contribute to the relief of her own heroes in Corsica. Consider that
you are as much a general as Tyrtæus was, and your poems (which, I am
confident, are much better than his ever were) may have as great an
effect as his. They may be the _coup de grace_ to the French troops in
that island, and Paoli, who reads English, will cause it to be printed
in every history of that renowned island.
"Without any joke, I wish you would comply with this request. In this
case you have only to send a corrected copy to me at Leeds, to Mr
Johnson in London, and I will take care to introduce it to the notice
of Mr Boswell by means of Mr Vaughan or Mrs Macauley, or some other of
the friends of liberty and Corsica in London. The sooner this is done
the better. Mr Turner regrets very much that it was not done some time
ago. I shall not tell you what I think of your poems for more than
twenty reasons, one of which is that I am not able to express it. We
are now all expectation at the opening of every packet from
Warrington.
"My piece on Perspective is nearly ready for the press. Come and see
us before it is quite printed, and I will engage to teach you the
whole art and mystery of it in a few hours. If you come a month after
I may know no more about the matter than anybody else. I am about to
make a bolder push than ever for the _pillory_, the _King's Bench
Prison_, or something worse. Tell Mr Aikin he may hug himself that I
have no connection with the Academy. On Monday next Mr Turner and I
set out on a visit to the Archdeacon at Richmond.
"With all our compliments to all your worthy family, I am, with the
greatest cordiality, your friend and admirer,
"J. Priestley."
Pasquale de Paoli, the Corsican patriot, whose struggles to secure the
independence of his native island had excited warm sympathy in England
and had enlisted the pen of Boswell, was at that time a refugee in this
country, having been defeated, after a stubborn resistance, by the
French under Count Vaux. The poem on "Corsica," one of the earliest and
most beautiful of Miss Aikin's productions, was written in 1768, at
about the period of the appearance of Boswell's _Account of Corsica_,
but it was first published in 1773 in a collection of her poems, of
which four editions, the first in 4to, the three others in 8vo were
printed in that year.
The copy seen by Priestley was in manuscript. Whether it was shown to
Boswell or to Paoli is not recorded.
The piece on Perspective was published in 1770, under the title of "_A
Familiar Introduction to the Theory and Practice of Perspective_. With
copperplates." He gave as his reason for writing it that, having
occasion to make drawings of philosophical instruments and apparatus he
had felt the need of a work treating of perspective. It will be seen in
the various editions of his works that the words "Priestley del" are
engraved at the left-hand corner of the copperplates of the
illustrations. The book had a considerable sale and was frequently
recommended by drawing-masters. A second edition appeared in 1782 and it
continued to be used well into the nineteenth century.
It is interesting to note that the first printed account of the use of
india-rubber for the purpose of erasing lead pencil marks occurs in the
preface to this work. It ran thus:--
"Since this work was printed off I have seen a substance excellently
adapted to the purpose of wiping off from paper the marks of black
lead pencil. It must therefore be of singular use to those who
practise drawing. It is sold by Mr Nairne, mathematical instrument
maker, opposite the Royal Exchange. He sells a cubical piece of about
half an inch for three shillings, and he says it will last several
years."
The "bolder push than ever for the _pillory_, the _King's Bench Prison_,
or something worse," probably refers to the anonymous pieces which he
published in support of "Wilkes and Liberty" in the course of the
memorable struggle between the freeholders of Middlesex and the House of
Commons concerning the rights of free representation by parliamentary
constituencies which at that time agitated the country. Wilkes had
shortly before the date of this letter been fined by the King's Bench
£1000 and sentenced to twenty-two months' imprisonment for publishing an
impious libel, and had been expelled from the House of Commons--to
which, however, he was repeatedly returned by the electors of Middlesex.
The Richmond visit to Archdeacon Blackburne, whose son had been at the
Warrington Academy, is memorable from the circumstance that on its
occasion Priestley first met Theophilus Lindsey, with whom he contracted
an intimate and lasting friendship, which greatly influenced the lives
and fortunes of both, and of which Priestley subsequently wrote that it
had been a source of more real satisfaction to him than any other
circumstance in his whole life.
The busy pamphleteer found time, however, to put together more ambitious
works than _Wilkes and Liberty_. The success of his _History of
Electricity_ induced him to attempt the compilation of the history of
all the branches of experimental philosophy, and he made proposals to
publish a _History of Discoveries Relating to Vision Light and Colours_.
The subscription to this work was not, however, sufficient to induce him
to proceed, and after a considerable outlay in the purchase of books and
other material the project was abandoned.
Priestley was, perhaps, the most industrious bookmaker of his age.
Boswell indeed dubbed him a "literary Jack-of-all-Trades," and he was
busy with proof-sheets even to the day of his death. In fact, the
closing act of his life, before he put his hand to his face to hide the
last flicker of the vital spark, was to make a correction in a
proof-sheet. He usually composed in shorthand, and much of this work was
done in the family circle, sitting by the parlour fire. Conversation
never disturbed him. Although his style is somewhat prolix, his language
is simple and direct and his meaning invariably clear. Charges that his
writings were hasty performances in nowise disturbed him. Indeed, he was
wont to say that some of those that were most hurriedly done were among
those that were best received. Whatever might have been the time he
spent on their composition he was confident that more would not have
contributed to their perfection in any essential particular, and about
anything farther he was never very solicitous. His object, he said, was
not to acquire the character of a fine writer but of a useful one.
Pecuniary gain was never the chief object of his work; several of his
books, indeed, were written with the prospect of certain loss. Many
writers before and since the great lexicographer have left us what they
have imagined to have been the secret of their success as literary
craftsmen, and have told us of the means by which they gained their
proficiency of composition and mastery of style. Priestley has no
pretensions to be considered a master of style; nevertheless, it is of
interest to learn how he acquired facility in writing the simple,
unaffected English which characterises his literary work. It came, he
said, from a practice of committing to writing as much as he could of
the sermons he heard, and of composing much in verse. With regard to the
sermons, he says:--
"This practice I began very early, and continued it until I was able
from the heads of a discourse to supply the rest myself. For, not
troubling myself to commit to memory much of the amplification, and
writing at home almost as much as I had heard, I insensibly acquired a
habit of composing with great readiness, and from this practice I
believe I have derived great advantage through life, composition
seldom employing so much time as would be necessary to write in long
hand anything I have published."
As regards the verses, he says:--
"I was myself far from having any pretension to the character of a
poet, but in the early part of my life I was a great versifier, and
this, I believe, as well as my custom of writing after preachers,
mentioned before, contributed to the ease with which I always wrote
prose."
If Priestley was not himself a poet, he was at least the cause of poetry
in another. Miss Aikin once told him that it was the perusal of some
verses of his that first induced her fledgling muse to soar--so that, he
adds, "this country is in some measure indebted to me for one of the
best poets it can boast of." No example of Priestley's abilities as a
"versifier" has come down to us, but in that dainty little sketch of the
Warrington society, by Miss Lucy Aikin, from which we have already
quoted, allusion is made to his accomplishment.
"Both _bouts rimés_ and _vers de société_ were in fashion with the
set. Once it was their custom to slip anonymous pieces into Mrs
Priestley's work-bag. One 'copy of verses,' a very eloquent one,
puzzled all guessers a long time; at length it was traced to Dr
Priestley's self."
To the man of science the special interest of Priestley's connection
with Leeds arises from the fact that he began there that fruitful series
of inquiries, relating to what he called "the doctrine of air," which
eventually raised him to the position of one of the greatest chemical
discoverers of his time. The house in which he first lived whilst at
Leeds was in Meadow Lane and adjoined the public brew house of Jakes and
Nell. He was thereby led, in the outset, to amuse himself by making
experiments on the "fixed air," or carbonic acid, which is largely
produced in the process of fermentation. When he removed to his second
house in Basinghall Street, on the site where the schools now stand, he
was under the necessity of making the fixed air for himself; and, as he
distinctly and faithfully notes in his various publications on the
subject, he was led to make one experiment after another until he
became, what he does not state, the greatest master of pneumatic
chemistry of his age.
When he began these experiments he tells us he knew very little of
chemistry. Indeed, he says he had in a manner no idea on the subject
before his attention was drawn to it in a course of lectures delivered
in the Warrington Academy by Dr Turner of Liverpool. But, as he says, on
the whole, this circumstance was no disadvantage to him, as in the
situation in which he found himself he was led to devise an apparatus
and processes of his own adapted to his peculiar views. If he had been
previously accustomed to the usual chemical processes he might not have
so easily thought of any other; and without new modes of operation he
thinks he should hardly have discovered anything materially new. His
means did not permit him to purchase expensive apparatus. Indeed, this
very circumstance materially contributed to his success by making his
apparatus so simple that his experiments could be readily repeated and
their accuracy thereby ensured.
His first contribution to Pneumatic Chemistry was published in 1772. It
was a small pamphlet on a method of impregnating water with fixed air,
which, being immediately translated into French, excited a great degree
of attention to the subject, and this was much increased by the
publication of his first experimental paper in the _Philosophical
Transactions of the Royal Society_.
Priestley's earliest method of impregnating water with carbonic acid
consisted in exposing it to the gas above the surface of fermenting
wort. This process was no doubt accompanied with many disadvantages and
the resulting solution could not have been very palatable. Later on he
adopted the method originally employed by Lane in 1709, although
apparently in ignorance of Lane's paper in the _Philosophical
Transactions_, of making the gas from chalk and sulphuric acid and
leading it directly into the water by means of a flexible tube provided
with an intercepting bladder to retain any solid or acid substance
projected from the effervescent materials in the generating flask. At
about this period increased attention was being paid to the question of
the supply of drinking water in the Navy, owing to the publication of
Irving's plan of making fresh water from sea-water by distillation, and
Priestley conceived the idea that if some ready means could be devised
of impregnating water with carbonic acid on shipboard the solution might
be useful as a preventive of sea scurvy.
Priestley brought his idea to the knowledge of the Duke of
Northumberland, and showed a sample of the impregnated water to Sir
George Savile, who introduced him to Lord Sandwich, at that time First
Lord of the Admiralty in Lord North's Administration. The Board of
Admiralty thought the matter was of sufficient importance to ask for a
report from the College of Physicians, and Priestley was requested to
appear before that body in order to explain and illustrate his process.
The report from the College was favourable, and in consequence two
war-ships were fitted with the apparatus.
The idea that scurvy, in common with other so-called putrid diseases,
was due to an insufficient supply of "fixed air" in the animal economy,
and that it might be cured by the administration of that gas, originated
with Dr Macbride about the middle of the eighteenth century, shortly
after Black had established the individuality of the gas, and it was
current doctrine with the faculty at the time of Priestley's
experiments. The reasons which Macbride gave in support of his
hypothesis are contained in his _Essays on Medical and Philosophical
Subjects_, and are sufficiently ingenious to be worth stating as
characteristic of much of the therapeutics of the time. Macbride assumed
that substances held together, and acquired the quality of firmness, by
virtue of containing a "cementing principle," which ensured the perfect
cohesion of their constituent particles, and that as putrefaction
resulted in the decomposition and disintegration of substances,
putridity was connected with the loss or disappearance of this cementing
or cohering principle. He found that "fixed air" was invariably produced
when animal and vegetable substances putrefy, that a greater amount of
fixed air is produced from vegetable substances than from animal
substances, and that animal and vegetable matters putrefy more rapidly
when mixed than when separate, and yield more fixed air in conjunction
than apart.
On the basis of these observations Macbride proceeded to explain the
well-established fact that a diet mainly composed of animal food is apt
to produce sea scurvy, the remedy for which is a sufficient supply of
fresh vegetables, by assuming that the virtue of the vegetables was due
to the evolution of a greater amount of carbonic acid in the process of
digestion, the fixed air so liberated in the body counteracting, by its
antiseptic powers, putridity in the circulating fluids.
We are not here concerned with the subsequent history of so-called
ærated or soda-water, as it came to be called, but it is worth noting
that Priestley's account of his process contains one remark which is not
without significance in view of latter-day developments. He says:--
"I do not doubt but that, by the help of a condensing engine, water
might be much more highly impregnated with the virtues of the Pyrmont
spring, and it would not be difficult to contrive a method of doing
it."
The manufacture of these waters was subsequently taken up by Priestley's
friend and _satellite_, as he called himself, Richard Bewley, of Great
Massingham, an apothecary, and the inventor of the well-known "mephitic
julep." Bewley appears to have discovered that the addition of a small
quantity of carbonate of soda to the water enabled it to absorb and
retain an increased quantity of carbonic acid, and to him, therefore, is
due the credit of first making what was long called "acidulous
soda-water." The receipt for its manufacture and use, given by Henry of
Manchester, is sufficiently quaint to be worth reproduction:--
"To prepare Mr Bewley's julep dissolve three drachms of fossil alkali
in each quart of water, and throw in streams of fixed air till the
alkaline taste be destroyed. This julep should not be prepared in too
large quantities, and should be kept in bottles very closely corked
and sealed. Four ounces of it may be taken at a time, drinking a
draught of lemonade or water acidulated with vinegar or weak spirit of
vitriol, by which means the fixed air will be extricated in the
stomach."
It is hardly to be supposed that the Royal Society Club in 1773 adopted
all the social manners and customs of the period. Nevertheless, its
members, who were among the most influential fellows of the Society,
were evidently greatly impressed with the merits of Priestley's
soda-water, since the Council of the Society were moved to reward its
discoverer with the Copley Medal.
In making the award on St Andrew's Day 1773, Sir John Pringle, then
President of the Royal Society, said:--
"For having learned from Dr Black that this fixed or mephitic air
could in great abundance be procured from chalk by means of diluted
spirits of vitriol; from Dr Macbride that this fluid was of a
considerable antiseptic nature; from Dr Cavendish that it could in a
large quantity be absorbed by water; and from Dr Brownrigg that it was
this very air which gave the briskness and chief virtues to the Spa
and Pyrmont waters; Dr Priestley, I say, so well instructed, conceived
that common water impregnated with this fluid alone might be useful in
medicine, particularly for sailors on long voyages, for curing or
preventing the sea scurvy."
To-day the Copley Medal is regarded as the highest award which it is in
the power of the Society to bestow, and certainly no man starts his
scientific career by acquiring it--not even for so signal an invention
as that of soda-water.
Whilst Priestley was at Leeds a proposal was made to him that he should
accompany Captain Cook in his second voyage to the South Seas. It
probably arose from his connection with the Admiralty in the matter of
his invention. He tells us that as the terms were very advantageous he
consented to it, the heads of his congregation agreeing to keep an
assistant to supply his place during his absence. But Mr Banks informed
him that he was objected to by some clergymen in the Board of Longitude,
who had the direction of this business, on account of his religious
principles. "Whether," said Huxley, in commenting on this circumstance
in the course of his speech at the unveiling of the Priestley statue in
Birmingham in 1874, "these worthy ecclesiastics feared that Priestley's
presence among the ship's company might expose his Majesty's sloop
_Resolution_ to the fate which aforetime befell a certain ship that went
from Joppa to Tarshish, or whether they were alarmed lest a Socinian
should undermine that piety which in the days of Commodore Trunnion so
strikingly characterised sailors, does not appear." The appointment was
given to Reinhold Forster, a man, as Priestley fully admitted, far
better qualified for the position.