gave his first lecture on Tuesday preceding my conclusion. I was an auditor in this case, the first time, and had an opportunity of surveying the audience. Amongst others of distinction the Bishop of Durham was present.

"In lecturing on optics I got six ribbands, blue, pink, lilac, and red, green, and brown, which matched very well and told the curious audience so. I do not know whether they generally believed me to be serious, but one gentleman came up immediately after and told me he perfectly agreed with me: he had not remarked the difference by candle light."

This letter concludes characteristically by "The rain has been 27 inches last year."

Like many students whose nerves are not easily affected, Dalton liked tobacco. A thorough explanation of its action on various constitutions seems to have hitherto escaped the research of medical men, most of them being content either to admire it, or to detest it, according as it may suit themselves. The following letter to Mr. John Rothwell gives Dalton's taste.

London, Jan. 10th, 1804.

"I was introduced to Mr. Davy, who has rooms adjoining mine in the Royal Institution: he is a very agreeable and intelligent young man, and we have interesting conversations in an evening: the principal failing in his character is, that he does not smoke. Mr. Davy advised me to labour my first lecture: he told me the people here would be inclined to form their opinion from it; accordingly I resolved to write my first lecture wholly; to do nothing but to tell them what I would do, and enlarge on the importance and utility of science. I studied and wrote for nearly two days, then calculated to a minute how long it would take me reading, endeavouring to make my discourse about fifty minutes. The evening before the lecture, Davy and I went into the theatre: he made me read the whole of it, and he went into the furthest corner; then he read it, and I was the audience; we criticised upon

each other's method. Next day I read it to an audience of about 150 or 200 people, which was more than were expected. They gave a very general plaudit at the conclusion, and several came up to compliment me on the excellence of the introductory. Since that time I have scarcely written anything; all has been experiment and verbal explanation. In general my experiments have uniformly succeeded, and I have never once faltered in the elucidation of them. In fact, I can now enter the lecture room with as little emotion nearly as I can smoke a pipe with you on Sunday or Wednesday evenings.

In 1807 he gave a similar course of lectures in Edinburgh, on which the following addressed to his friend, the Rev. W. Jones, may be read with interest.

As the time I proposed to be absent is nearly expired, and as my views have recently been somewhat extended, I think it expedient to write you for the information of enquirers. Soon after my arrival here I announced my intention by advertisement of handbills; I obtained introduction to most of the professional gentlemen in connection with the college, and to others not in that connection, by all of whom I have been treated with the utmost civility and attention; a class of eighty appeared for me in a few days; my five lectures occupied me nearly two weeks; they were finished last Thursday, and I was preparing to leave the place, and return by Glasgow, to spend a week. But several of the gentlemen who had attended the course represented to me that many had been disappointed in not having been informed in time of my inten tion to deliver a course, and that a number of those who had attended the first course would be disposed to attend a second. I have been induced to advertise for a second, which, if it succeeds, will commence on Wednesday, the 22nd, and be continued daily, till the conclusion. This will detain me a

week yet; I then set off for Glasgow, where I may be detained for a week or more, so that I see no probability of reaching Manchester before the beginning of May, to which I look forward with some anxiety. Hitherto I have been most highly gratified with my journey; it is worth coming 100 miles merely to see Edinburgh. It is the most romantic place and situation I ever saw; the houses touch the clouds; at this moment I am as high above the ground as the cross on St. James's spire; yet there is a family or two above me ; in this place they do not build houses side by side as with you, they build them one upon another, nay, they do what is more wonderful still, they build one street upon another; so that we may in many places see a street with the people in it, directly under one's feet, at the same time that one's own street seems perfectly level and to coincide with the surface of the earth. My own lodgings are up four flights of stairs from the front street, and five from the back. I have just 100 steps to descend before I reach the real earth. I have a most extensive view of the sea; at this moment I see two ships; and mountains across the Firth of Forth, at the distance of thirty miles; to look down from my windows into the street at first made me shudder, but I am now got so familiar with the view, that I can throw up the window and rest on the wall, taking care to keep one foot as far back in the room as I can, to guard the centre of gravity. The walks about Edinburgh are most delightfully romantic. The weather is cold; ice every morning, and we had a thick snow a few days ago. Upon walking up on to an eminence I observed all the distant hills white; the nearer ones speckled; I saw five or six vessels just touching the horizon; they seemed to be about ten or twelve miles off, and their white sails looked like specks of snow on the sea. I saw a dozen or two at anchor in the river, and a most charming view of the Fifeshire hills on the other side of the Firth. Adieu. My best regards to you all."

J. DALTON.

Again, from London, December 27th, 1809, wh another course of lectures, he writes to Mr. Jones, a pleasant gossip about his fellow-travellers :

"On Tuesday I spent greater part of the day they call it here) with Mr. Davy in the laborator Royal Institution. Sir I. Sebright, M.P., who is a student of chemistry, was present. We had a lon sion. In the evening I walked three miles into the Pickford's, to look after my boxes; I found them th as they promised to send them next day I did not tal They disappointed me. On Wednesday I attend Bond's lecture on astronomy, and prepared for m next day. On Thursday, at two, I gave my first Mr. Pearson, a former acquaintance, went home after the lecture, and we had a long discussion on me Mr. Davy had invited me to dine with the club of the Society, at the Crown and Anchor, at five o'clock, bu detained till near six; I got there and called Davy was over; the cheese was come out. I went, there the nearest eating-house I could find to seek a dinner ing in at a window I saw a great heap of pewter pla some small oblong tables covered with cloths. I went asked for a beefsteak; "no." What can I have? "boiled Bring some immediately. There was nothing eatable in the room, but in three minutes I had placed befor large pewter plate covered completely with a slice of lent boiled beef swimming in gravy, two or three po bread, mustard, and a pint of porter. Never got a dinner. It cost me 11d. I should have paid 7s. Crown and Anchor. I then went to the Royal Societ heard a summary of Davy's paper on chemistry, and Home's on the poison of the rattlesnake: Sir J. Banks chair. Davy is coming very fast into my views on che subjects. On Friday I was preparing for my second le I received a visit from Dr. Roget. On the evening

attacked with sore throat. I sweated it well in the night with cloathing, but it was bad on Saturday, and I was obliged to beg a little indulgence of my auditors on the score of exertion. However, I got through better than I expected. I kept in on Sunday and Monday and got pretty well recruited. On Tuesday I had my third lecture, after which I went to dine at a tavern to meet the chemical club. There were five of us, two of whom were Wollaston and Davy, secretaries of the Royal Society; we had much discussion on chemicals. Wollaston is one of the cleverest men I have yet seen here. To-day, that is Thursday (for I have had this letter two or three days in hand), I had my fourth lecture. I find several ingenious and inquisitive people of the audience. I held a long conversation to-day with a lady on the subject of rain-gauges. Several have been wonderfully struck with Mr. Ewart's doctrine of mechanical force. I believe it will soon become a prevalent doctrine. I should tell Mrs. J. something of the fashions here, but it is so much out of my province, that I feel rather awkward. I see the belles of New Bond-street every day, but I am more taken

up

with their faces than their dresses. I think blue and red are the favourite colours. Some of the ladies seem to have their dresses as tight round them as a drum, others throw them round them like a blanket. I do not know how it happens, but I fancy pretty women look well any how.

I am very regular with my breakfast, but other meals are so uncertain that I never know when or what. Hitherto I have dined at from two to seven o'clock; as for tea I generally have a cup between nine and ten, and, of course, no supper. I am not very fond of this way of proceeding. They say things naturally find their level, but I do not think it is the case in London. I sent for a basin of soup the other day before I went to lecture, thinking I should have a good threepenny worth, but I found they charged me one shilling and ninepence for a pint, which was not better than some of our