Though my philosophical labours are nearly over, I am glad to hear what is pa.s.sing in that region in which I once moved, though what I then did seems for the present to be overlooked and forgotten. I am confident, however, as much as I can be of anything, that notwithstanding the almost universal reception of the new theory, which is the cause of it, it is purely chimerical, and cannot keep its ground after a sufficient scrutiny, which may be deferred, but which must take place in time. I am glad to find that Mr.

Cruikshank in England, as well as chemists in France, begin to attend to my objections, though the princ.i.p.al of them have been published many years; but, as you say, many will not read, and therefore they cannot know anything that makes against the opinions they have once adopted. Bigotry is not confined to theology.

The experimental work for the year was not very great. Probably this was the result of his general physical weakness and in part it was due to his preoccupation with literary labours. However, he did write out his results, obtained on heating "finery cinders and charcoal" and thus emphasized the gaseous product of which he observes--

It cannot be denied, however, that this gaseous oxyd of carbon (CO) is _inflammable_ ... and is essentially different from all other oxyds, none of which are combustible.

Along in the month of November he wrote a vigorous protest against Cruikshank's explanation of the mode of formation of carbon monoxide. In this polemic he of course threw into prominence his precious phlogiston, the presence of which seemed unnecessary--but this was not so thought by the Doctor, who also favored the _Medical Repository_ with observations on the conversion of iron into steel, in which there is but a single reference to phlogiston, but unfortunately this single reference spoils the general argument and the correct and evident interpretation of the reaction. It reads as follows:

Iron is convertible into steel by imbibing only _phlogiston_ from the charcoal with which it is cemented.

There are abundant correct observations. Their interpretation sadly enough is very false, all because of the persistent introduction of phlogiston where it was not essential.

Priestley advised Rush that because of an unhealthy season he had suffered very much from ague, and said,--

Tho' I was never robust, I hardly knew what sickness was before my seizure in Philadelphia, but the old building has since that had so many shocks, that I am apprehensive it will ere long give way.

But I have abundant reason to be satisfied, and shall retire from life _conviva satur_.

Devotion to work was on the part of Priestley, something marvelous. As his son and daughter-in-law were drawn to Philadelphia in February, 1803, they carried their father with them. He was rather indisposed to this, yet he disliked remaining alone at home notwithstanding the printing of the Church History required considerable personal attention.

The marvelous part of it all was that while in Philadelphia, on this his fourth and last visit, while he fraternized with congenial souls and even presented himself at various social functions, he yet found leisure to print his little volume ent.i.tled "Socrates and Jesus Compared,"

which gave much pleasure to President Jefferson, so much indeed that he hoped Priestley would,--

take up the subject on a more extended scale, and show that Jesus was truly the most innocent, most benevolent, the most eloquent and sublime character that has ever been exhibited to man.

Jefferson's genuine approval of his effort was balm to Priestley's soul.

He, of course, wrote Lindsey and Belsham about it; yes, copied the letter of Jefferson and sent the same to them with the comment,--

He is generally considered as an unbeliever. If so, however, he cannot be far from us, and I hope in the way to be not only _almost_, but _altogether_ what we are.

It was February 28, 1803, that the august members of the American Philosophical Society resolved:

That this Society will dine together on Sat.u.r.day next, and that J.

B. Smith, Wistar, Williams, Hewson & Vaughan be a Committee to make the necessary arrangements for that purpose and to request Dr. Priestley's company, informing him that the Society are induced to make the request from their high respect for his Philosophical Labours & discoveries, & to enjoy the more particular pleasure of a social meeting--The Dinner to be prepared at the City Tavern or Farmer's Hotel.

It was this resolution which caused notices, such as the following to go out to the distinguished membership of the venerable Society--

Philadelphia, March 2, 1803

Sir: You are hereby invited to join the other members of the American Philosophical Society, in giving a testimony of respect, to their venerable a.s.sociate Dr. Joseph Priestley, who dines with them on Sat.u.r.day next at Francis' Hotel--Dinner on table at 3 o'clock.

C. Wistar J. Williams J. R. Smith T. T. Hewson J. Vaughan Committee

An answer will be called for tomorrow morning.

DR. RUSH

It was a very dignified and brilliant company. Law, medicine, theology, science, commerce represented by very worthy and excellent gentlemen.

And, among them sat the modest, una.s.suming, versatile Priestley. That he was happy in his surroundings there is ample reason to believe. He loved to be among men. He, too, was appreciated and eagerly sought because of his winning ways, his tolerance and liberality. He was moderately convivial though

He said that one gla.s.s of wine at dinner was enough for an old man, but he did not prescribe his own practice as an universal rule.

About eight weeks were spent in the City. On return to the dear country home the doctor took up his various duties and burdens, but the infirmities of age were often alluded to by him, and they no doubt delayed all of his work, which was further aggravated by a dangerous fall on his left hip and strain of the muscles of the thigh. He was extremely lame and for some time went about on crutches, which held him out of his laboratory. To him this was very trying. But he persisted. He was truly a splendid example for the younger aspirants for scientific honors. During the year he entered on a controversial article with his old friend Erasmus Darwin upon the subject of _spontaneous combustion_, and subsequently communicated to the _Medical Repository_ an account of the conversion of salt into nitre. He had positive knowledge of this fact for quite a little while, and upon the occasion of a visit by Dr.

Wistar, told the latter concerning this with the request that no mention be made of it, evidently that he might have opportunity for additional confirmation. However, very unexpectedly, Dr. Mitchill published something of a similar character, therefore Priestley believing that he ought "to acquaint experimentalists in general with all that I know of the matter," announced that in 1799 when experimenting on the formation of air from water,

having made use of the same salt, mixed with snow, in every experiment, always evaporating the mixture the salt was recovered dry. I collected the salt when I had done with it, and put it into a gla.s.s bottle, with a label expressing what it was, and what use had been made of it.

Subsequently he treated this salt, after many applications of it, with sulphuric acid, when he remarked--

I was soon surprized to observe that _red vapours_ rose from it.

An examination of another portion of the salt showed--

that when it was thrown upon hot coals ... it burned exactly like nitre.

So it was a conversion of sodium chloride into sodium nitrate. That this change must have come from the _snow_ with which it had been dissolved, could not be doubted, and he further observed--

Now in the upper regions of the atmosphere ... there may be a redundancy of inflammable air ... and a proportion of dephlogisticated air. In that region there are many electrical appearances, as the _aurora borealis_, falling stars &c; in the lower parts of it thunder and lightening, and by these means the two kinds of air may be decomposed, and a highly dephlogisticated nitrous acid, as mine always was, produced. This being formed, will of course, attach itself to any _snow_ or _hail_ that may be forming ... confirming in this unexpected manner, the vulgar opinion of nitre being contained in snow.

This seems to be the last communication of this character which came from the Doctor's pen.

He was in despair relative to the academy which had ever been his hope for the College which in his early years in Northumberland he prayed might arise and in which he would be at liberty to particularly impart his Unitarian doctrines.

An interesting item relative to the Academy appeared in the _Aurora_ for April 1st, 1803. It shows that State aid for education was sought in those early days. It is a report, and reads--

A REPORT of the Committee to whom was referred the Pet.i.tion of Thomas Cooper, on behalf of the Northumberland Academy, praying legislative aid. The report states that Thomas Cooper appeared before the Committee and stated that upward of $4000 had been expended on the building appropriated to that inst.i.tution. That the debts due thereon amounted in the whole to near $2000. That Dr. Joseph Priestley had the power of disposing of a very valuable library consisting of near 4000 volumes of scarce and well chosen books in various branches of literature and science, to any public seminary of learning in the United States, which library, the said Dr. Priestley was desirous of procuring as a gift to the Northumberland Academy, provided that inst.i.tution was likely to receive substantial a.s.sistance from the legislature, so as to be enabled to fulfil the purposes of its establishment,

That the Trustees would have no occasion to ask of the legislature on behalf of that Academy, a subscription greater than a few individuals had expended, and were still ready and desirous of contributing thereto; and suggest it to your Committee, that if out of the monies due from the County of Northumberland to the State a sufficient sum was granted to exonerate the Academy from debt, no more would be wanted in the future to effect the purposes of that inst.i.tution, than a sum equal in amount to the value of the library proposed to be furnished by Dr. Priestley; such value to be fixed by a person appointed for the purpose by the legislature.

The Committee was of the opinion that it would be expedient for the legislature to coincide with the suggestion of Thomas Cooper and so recommended to the Legislature. Their report was adopted, 39 to 31. It was strongly advocated by Jesse Moore, Esq., General Mitch.e.l.l and N. Ferguson from the city. It was opposed by Jacob Alter from c.u.mberland, who declared that although there were a great many public schools and colleges and places of that kind scattered over the State, he never knew any good they did, except to breed up a set of idle and odious lawyers to plague the people!

At this particular time there still existed confiscated land from the sale of which revenue was derived, and this income it had been agreed upon should be devoted to the erection and support of academies throughout the State. Later this scheme was discontinued. But, Dr.

Priestley was not so enthusiastic as formerly. He was occupied with the Church History, three volumes of which were in print, and it was expected that the fourth volume would follow shortly thereafter.

However, his health was precarious. He could not eat meats, and lived chiefly on broths and soups, saying,--

The defect is in the stomach and liver, and of no common kind. If I hold out till I have finished what I have now on hand, I shall retire from the scene, satisfied and thankful.

This was written in August, and the Doctor stuck bravely to his literary labors. A few months later he wrote Lindsey,--

I really do not expect to survive you.

Yet, he also entertained the thought that he might,--

a.s.sist in the publication of a whole Bible, from the several translations of particular books, smoothing and correcting them where I can.

January of 1804 brought him many interesting, splendid and valuable books from friends in London. He was overjoyed on their arrival.

Promptly he gave himself to their perusal because his deafness confined him to home and his extreme weakness forbade any excursions. Then the winter kept him from his laboratory, and his sole occupation was reading and writing. He entertained a variety of plans, proceeding with some but in the midst of these tasks of love--in the very act of correcting proof, he quietly breathed his last! It was Monday, February 6, 1804, that Thomas Cooper, the devoted friend of Priestley, wrote Benjamin Rush:--

Dear Sir:

Mr. Joseph Priestley is not at present in spirits to write to his friends, and it falls to my lot therefore to acquaint you that Dr.

Priestley died this morning about 11 o'clock without the slightest degree of apparent pain. He had for some time previous foreseen his dissolution, but he kept up to the last his habitual composure, cheerfulness and kindness. He would have been 71 the 24th of next month. For about a fortnight there were symptoms of dropsy owing to general debility: about two days before his death, these symptoms disappeared, and a troublesome cough came on perhaps from a translation to the chest.