Part 16

[62] On that day, (Dr. Johnson said) as it was an unusual deprivation, he found himself disinclined, and unable to attend steadily to the work that led him to refuse the invitation. He walked about his library occasionally looking over first one book and then another until about four o’clock when weary of staying within he went to a tavern to dine. Dr. Johnson had for a long time a dislike to Dr. Priestley who bore two of the characters most in disrepute with Dr. Johnson, that of a whig and a dissenter. Dr. Priestley’s pursuits also consisting so largely of heterodox theology, which Dr. Johnson abominated, and experimental philosophy which he heartily despised, they had hardly a common point of union. Toward the latter part of Johnson’s life, they met; and upon the friendly terms that ought to obtain between two men, who, each in their way, deserved so well of the republic of letters.

The first edition of his history of Electricity, was in 1767: it went through another edition in 1769, and a third in 1775. It was published at a very happy time, when electricity was a favourite object of attention to many respectable men of science then living, and it contributed in a great degree to turn the public attention toward the study of these phenomena. Very much of what has been done since may be fairly attributed to the popularity given to this branch of experimental philosophy by Dr. Priestley. Nor did he confine himself to a mere narration of the labours of others; the second volume contains many new experiments of his own, and some of them form very curious and important additions to the stock of electrical knowledge.[63] The discoveries of the last thirty years, particularly including those of Galvanic Electricity, are so numerous, and so dispersed in volumes difficult to be procured, that a continuation of this history is a desideratum in the scientific world; at one time there was an expectation of seeing it from the pen of Mr. Nicholson, whose general knowledge, and industry, as well as his attention to this branch of philosophy in particular, render him peculiarly qualified for the task. But the proposals he communicated to Dr. Priestley, on the subject, were not pursued to effect.[64]

[63] Dr. Priestley among his other experiments on electricity first ascertained the conducting power of charcoal and the calcination and vitrification even of the most perfect metals by the electric spark. He seems first to have used large batteries, which M. Van Marum and his associates have carried to such extent.

The solutions of the metals, the gasses produced and the circumstances which accelerate and prevent these effects in Galvanic processes with the pile of Volta, as detailed by Dr. Priestley in his paper on this subject in Nich. Journ. for March 1802 p. 198 form very important additions to the mass of knowledge respecting the Galvanic fluid. Nor are his discoveries in pneumatic electricity, of the conversion of oils, spirit of wine and the alkaline gass into inflammable air or hydrogen of less moment.

[64] Dr. Bostock, who seems to have many requisites to qualify him as the historian of particular branches of science, has published a good attempt toward the history of Galvanism in Nicholson’s Journal.

These histories of detached branches of Science, would not only be highly useful, but they may be considered as in some measure necessary to the accurate pursuit, and advancement of science itself. They are not only useful for the purpose of shewing the discoveries that have been made, and the time of their publication, the ideas that appear to have suggested them, the persons to whom we are indebted for them, and their effect on the spirit of enquiry at the time, but they prevent a man of science from being led into mistakes, from doing what has been already done, from suggesting what has been already published, and from ignorantly claiming to himself the merit due to the labours of a predecessor. Books are now so multiplied, in languages so various, obtained with so much difficulty, and at an expence so far exceeding the usual means of scientific men, that those who like Dr. Priestley fully and faithfully execute a work of this description are real benefactors to mankind.[65]

[65] The transactions of the various academies and philosophical societies in Europe amount at least to 1000 volumes in quarto. The royal society of England in 1665 led the way to similar institutions.

The history of ELECTRICITY was composed by Dr. Priestley in one year. The three editions of the work in less than eight or nine years sufficiently shew that, in the opinion of men of science, it was well composed: otherwise the celerity of its composition, would no doubt derogate from, instead of adding to, the well earned reputation of the author; and rather tend to shew that he was too careless or too conceited to take the necessary pains and employ the necessary time to make it fit for public inspection. Every man owes to the public, that if he professes to instruct them, he should dedicate as much labour as the subject demands, or at least as much time as it is in his power to devote to it. I fully accede to the ingenious correction of the _nonum prematur in Annum_, suggested by the witty Dr. Byrom of Manchester; but something of the _Limæ Labor_, respect for the tribunal of the public demands of every man who appears before them in the character of an author. Dr. Priestley has in more instances than one, been accused of unnecessary if not of culpable rapidity in his literary compositions: but he never professed to be a fine writer; he never sought after the beauties of stile; and his common language was sufficiently neat and expressive, to communicate the facts and the arguments upon which it was employed. It is also to be remarked, that the facility of composition which he acquired from long practice, made that labour light to him, which would have been too much for a less skilful and a less experienced composer. In many instances indeed of his rapid publications, he had not to _seek_ for arguments, but to express in his unornamented and unaffected manner, the ideas that forced themselves upon him relating to a subject previously considered and upon which he had long made up his mind.

The History of Discoveries respecting LIGHT and COLOURS published in 1772 was a more difficult task, nor did it meet with equal encouragement. Sir Isaac Newton’s important labours in this branch of science, could not be fully comprehended without a portion of mathematical knowledge not even then so common as formerly, among the philosophers of the day. Mathematical studies seem to have in themselves very little to interest, compared with other literary pursuits; although by long attention and habit, that interest may be excited and kept up. It was about this time that the popular phenomena of chemistry and electricity more decidedly took their stand in the field of science, and irresistably seized hold on the attention of the world: phenomena, highly amusing in themselves, strongly attractive from their novelty, of evident and immediate application, and that promised an incalculable harvest of honourable and useful discovery, to such as would become their votaries. Little had been done in this department of philosophy, little previous knowledge was required to comprehend all that was known, and those who were unable to read a page of Sir Isaac Newton with profit, could easily mix an acid and an alkali, or turn the wheel of an electrical apparatus.

By this time too, it had been discovered, that there were other powers in nature that must be called in to explain appearances, which the mechanical and corpuscular philosophy had endeavoured to elucidate in vain. Such were magnetism, electricity and chemistry. It began to be found out, that the science of calculation, was but an aukward handmaid to their sister branches of natural philosophy, while physiology, laughed outright at the clumsy addresses of her mathematical admirers, from Borelli to Keill.

The discoveries therefore relating to light and colours, at the time when Dr. Priestley proposed his history, being intimately associated with the study of the mathematics, and the profound investigations of Sir Isaac Newton, were out of the beat of the less laborious, but more fashionable philosophy of the day; and were not so generally interesting to the Sciolists and Amateurs. Hence the work in question, though treated in a very entertaining and popular manner, and by no means crouded with reference to Diagrams or abstruse discussions, was not popular even among that class of readers, who might reasonably be calculated on, as the purchasers of such a performance. The subscribers indeed were sufficiently numerous, and respectable, but by far the majority were defaulters in respect of payment. It did not pay the bookseller: and of course still less did it recompence Dr. Priestley in a pecuniary point of view, especially as he had gone to considerable expence with a view to the completion of his extended plan. To him indeed, though pecuniary loss was a serious evil, pecuniary profit was a consideration of small importance: his motives to literary labour seem uniformly to have arranged themselves as follows, utility, reputation, profit.

The work in question is certainly too brief, considering the importance of the subject: many parts of it, the theory of Huygens, Euler, and Franklin for instance, seem to have merited more discussion. That all the phenomena of light depend on the Sun, as the reservoir, whence all the emanations of that fluid to the various parts of the system are supplied, the lighting of a candle is alone sufficient to refute. The facts discovered to us by modern Chemistry will suggest a great many other doubts of the doctrines respecting light, which were regarded as well established when Dr. Priestley’s book was written. But it was a faithful account of the knowledge of the day, and an unprejudiced tribute to the reputation of those philosophers who had from time to time extended the boundaries of science on the subjects treated of.

Not a little has been added to the mass of facts then published, by the subsequent experiments of Dr. Priestley himself, and his fellow labourers in the Chemistry of the Gasses: and notwithstanding the experiments of Sir Isaac Newton and his predecessors, the theory of light and colours is not yet rested upon facts sufficiently numerous, and decisive to satisfy the enquiries dictated by the present state of knowledge.

But with all these disadvantages, the work has nevertheless maintained its ground, for we have no where else so systematic, and compleat, though brief an account of what had been made known to the world on this important branch of scientific inquiry. It will always remain a valuable performance; and to the author an honourable one, from the knowledge and ability required in its compilation, from the fairness of the account it gives, and the entertaining statement of facts and suggestions interspersed through the book.

It is greatly indeed to be wished, that these histories should be continued on the plan which Dr. Priestley has adopted. So that all the prominent facts should be collected in the order of their discovery, and a full view be given of the ground already gone over. Abridgments, do not answer this purpose; the theories that dictated the experiments are not detailed, their truth or their fallacy cannot be judged of, and sufficient merit is not attributed to the labours of the discoverer, or the bearings of his facts on his theory, sufficiently explained. To attain gradually to the summit of the temple of science, we must not only build on the foundations of our predecessors, but know somewhat of their intentions at the time of laying them.

The minor treatises of Dr. Priestley on electricity, perspective and natural philosophy, have this discrimination of character, that they are more calculated to allure young people to the study of those subjects than almost any of the introductions which have either preceded or succeeded. Philosophy is made, not an abstruse science, but a delightful amusement. Indeed it was the fort of Dr. Priestley to make knowledge intelligible and popular, and treat it in such a way, as to invite rather than deter, those who were inclined to enter upon these delightful pursuits. The plainness and simplicity of his syllabus, the amusing complexion of the Phenomena, by which he illustrates his doctrines, and the facility with which the one can be made, and the other comprehended, affords a very useful example to those who may have the same object hereafter in view. This was doubtless, owing to his long experience as a teacher: and his success in that capacity among his pupils, with the electrical machine, and the air pump, is full evidence of the practical utility of his plans of instruction.

_Catalogue of Dr. Priestley’s smaller pamphlets and uncollected papers on philosophical subjects._

_Nicholson’s_ } _Journal._ } _new series._ }

V. 1 p. 181. Reply to Mr. Cruikshank’s. Ibid 198. Experiments on the Pile of Volta. V. 2 p. 233. On the conversion of iron into steel. V. 3 p. 52. On air from finery cinder and charcoal. V. 4 p. 65. Farther reply to Mr. Cruikshank’s.

_Amer. Trans._

V. 4 p. 1. Experiments and observations relating to the analysis of atmospherical air. V. 4 p. 11. Farther experiments relating to the generation of air from water. Ibid p. 382. Appendix to the above articles.

_Ib. Vol._ V. {p. 1. Experiments on the transmission { of acids and other liquors in the { form of vapours over several substances { in a hot earthen tube. Republished { {p. 14. Experiments on the change of { place in different kinds of air { through several interposing substances. { 21. Experiments relating to the absorption { of air by water. { { 28. Miscellaneous experiments relating { to the doctrine of phlogiston. together. { { 36. Experiments on the production of { air by the freezing of water. { { 42. Experiments on air exposed to { heat in metallic tubes.

_New-York Med. Repos._ _Title and Date._

Vol. 1 p. 221. Considerations on the doctrine of Phlog. and the Decomp. of water. (Pamphlet) 1796. Ibid p. 541. Part 2d of do. (Pamphlet 1797.) Vol. 2 p. 48. (Pamphlet) to Dr. Mitchell. Ibid p. 163. (Pamphlet) on Red Precipitate of Mercury as favourable to the doctrine of Phlogiston, July 20, 1798. Ibid p. 263. Experiments relating to the calces of metals communicated in a fifth letter to Dr. Mitchell. October 11, 1798. (Pamphlet.) Ibid p. 269. Of some experiments made with ivory black and also with diamonds. (Pamphlet) 11 October, 1798.

Ibid p. 383. On the phlogistic theory, January 17, 1799. (Pamphlet.)

Ibid p. 388. On the same subject. February 1, 1799.

Vol. 3 p. 116. A reply to his antiphlogistian opponents, No. 1.

Vol. 4 p. 17. Experiments on the production of air by the freezing of water.

Ibid p. 135. Experiments on heating Manganese in inflammable air.

Ibid p. 247. Some observations relating to the sense of hearing.

Vol. 5 p. 32. Remarks on the work entitled “A brief history of epidemic and pestilential diseases,” May 4, 1801.

Ibid p. 125. Some thoughts concerning dreams.

Ibid p. 264. Miscellaneous observations relating to the doctrine of air, July 30, 1801.

Ibid p. 390. A reply to Mr. Cruikshank’s observations in defence of the new system of chemistry, 5 Vol. Nicholson’s Journal p. 1, &c.

Vol. 6 p. 24. Remarks on Mr. Cruikshank’s experiments upon finery cinder and charcoal.

Ibid p. 158. Observations on the conversion of iron into steel.

Ibid p. 271. Additional remarks on Mr. Cruikshank’s experiments on finery cinder and charcoal, November 15 1802.

APPENDIX, NO. 2.

_Of Dr. Priestley’s Metaphysical Writings._

The principal source of objection to Dr. Priestley in England, certainly arose from his being a dissenter; from his opposition to the hierarchy, and to the preposterous alliance, between Church and State: an alliance, by which the contracting parties seem tacitly agreed to support the pretensions of each other, the one to keep the people in religious, and the other in civil bondage. His socinian doctrines in theology, and the heterodoxy of his metaphysical opinions, though they added much to the popular outcry raised against him, were not less obnoxious to the generality of Dissenters, than to the Clergy of the Church of England. Nor is it a slight proof of the integrity of his character, and his boldness in the pursuit of truth, that he did not hesitate to step forward the avowed advocate of opinions, which his intimate and most valuable friends, and the many who looked up to him as the ornament of the dissenting interest, regarded with sentiments of horror, as equally destructive of civil society and true religion.

The extreme difference observable between the apparent properties of animal and inanimate matter, easily led to the opinion of something more as necessary to thought, and the phenomena of mind, than mere juxta position of the elements, whereof our bodies are composed. The very antient opinion also of a state of existence after death, prevalent in the most uncivilized as well as enlightened states of society, confirmed this opinion of a separate and immortal part of the human system: for it was sufficiently evident, that no satisfactory hopes of a futurity after death, could be founded on the perishable basis of the human body. It is only of late days, and from the extension of anatomical and physiological knowledge, that the theory, and the facts of animal organization have been at all understood; and without the conjunction of physiology with metaphysics, the latter would have remained to eternity, as it has continued for ages, a mere collection of sophisms, and a science of grammatical quibbling. The doctrine of a future state, and that of an immaterial and immortal soul, became therefore mutual supports to each other; and herein the civil power willingly joined in aid of the dogmas of metaphysical theology, from observing the convenience that might arise in the government of civil societies, from inculcating a more complete sanction of rewards and punishments for actions in this life, by means of the dispensations in a life to come. Other causes also gave an universal preponderance to the theory of the human soul. It became, for the reasons above mentioned, not only a favourite doctrine with churchmen and statesmen, but the self delusions among the vulgar, respecting supposed appearances after death, rendered it also a _popular_ doctrine. Indeed, in every age, and in every country, the priesthood have found it so powerful an engine of influence over the minds of the people, and in too many cases, so, fruitful a source of lucrative imposture, that its prevalence is not to be wondered at, wherever artificial theology has been engrafted on the simplicity of true religion, and supported by an established clergy. Of Popery, which yet remains the prevailing system of the christian world, it is doubtless the corner stone; and even under every form of ignorant and idolatrous worship throughout the globe, it is the main source of power and profit to that class of society, which regulates the religious opinions, rites and ceremonies of the country. Not that I would insinuate, that the belief of a separate soul, like some other opinions that might be mentioned, has been generally taught by professors who disbelieve it; for plausible arguments are not wanting, to give it that currency which it has so long received among the wisest and the best of men: nor that an established priesthood of any age or country, or of any religion, is a mere compound of fraud and imposture, for I well know that the wise and the good are abundant in this class of society, as well as in others. But even such men are liable to the common infirmities of human nature; they cannot be indifferent to their rank in society, or the means of their subsistence; it is not every college youth, that is able or willing to weigh “the difficulties and discouragements attending the study of the Scriptures,” so forcibly pointed out in the melancholy pamphlet of Bishop Hare: nor is it every professor of Christianity, who doubts of the doctrines he has undertaken to teach, that has fortitude enough to follow the noble example of Theophilus Lindsey, and John Disney. Hence we may take for granted, that those opinions will be admitted the most readily, and enforced the most willingly, which contribute to the influence of that order, which the professors have been induced by choice, or compelled by necessity, to wed for life. Choice indeed, at least that kind of choice, which depends on a well-grounded conviction of the object chosen being the means of superior usefulness, has little to do in this business. For though the clergy of the church of England severally declare that they are moved by the Holy Ghost to take upon them the clerical character, is there one among them in the present day (Bishop Horsely perhaps excepted) who would venture to defend this declaration in the sense originally intended? It is a fact notorious, that the candidates for holy orders, regard the profession of Divinity as they would that of Physic or Law, a fair and reputable means of gaining a livelihood, by performing those duties which are considered as necessary to the well being of society. It is a fact too, equally notorious, that wherever theological opinions (like that of the human soul) have been fit and liable to be made subservient to the temporal profit or influence of the clergy, that use has been so made of them by the ambitious and designing part of the profession, and the rights of the people have been encroached upon, to serve the interest of the Hierarchy. Nor is it the established clergy alone that some of the preceding remarks will apply to: much bigotry among the clergy of the dissenting interest, may fairly be ascribed to similar causes, though by no means operating in the same degree.

But important as this doctrine is to the clerical order in political societies, some latitude of doubt and even of denial, has been conceded in England to the known friends and adherents of the established system in that country. This is the more to be wondered at, as they have generally considered a dissonance of opinion among their own order, more fatal to the common interest, than the attacks of their avowed enemies. Thus, more notice was taken of the Arian heterodoxy of Dr. Clarke, than of the avowed infidelity of Collins, Tindal, Toland, Coward, and other writers of that class, who published about the same period.