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OBSERVATIONS.

July 31. At one P. M. the Start bore WNW. distant six leagues.
August 1. The water appears luminous in the ship's wake.

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2. The temperature of the water is taken at eight in the morning and at eight in the evening.

-6. The water appears less luminous.

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Formegas SW. dist. 32 deg. St. Mary's SWS. 33 leagues.

8. From this date the temperature of the water is taken at eight in the morning and at six in the evening.

10. Moonlight, which prevents the luminous appearance of the water. 11. A strong southerly current.

Ditto. From this date the temperature of the air and water was

taken at noon, as well as morning and evening.

16. Northerly current.

19. First saw gulph weed.

21. Southerly current.

-22. Again saw gulph weed.

rose.

24. The water appeared luminous in a small degree before the moon

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- 2.

A little more light in the water.

-4. No gulph weed to-day. More light in the water.

-5. Some gulph weed again.

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6. Little light in the water. A very hard thunder-gust in the night. -7. Little gulph weed.

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- 9. Little gulph weed. Little light in the water last evening.

-10. Saw some beds of rock-weed; and we were surprised to observe the water six degrees colder by the thermometer than the preceding noon.

This day (10th) the thermometer still kept descending, and at five in the morning of the 11th, it was in water as low as 70, when we struck soundings. The same evening the pilot came on board, and we found our ship about five

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degrees of longitude a-head of the reckoning, which our captain accounted for by supposing our course to have been near the edge of the gulph stream, and thus an eddy-current always in our favor. By the distance we ran from Sept. 9, in the evening, till we struck soundings, we must have then been at the western edge of the gulph stream, and the change in the temperature of the water was probably owing to our suddenly passing from that current into the waters of our climate.

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On the 14th of August the following experiment was made. The weather being perfectly calm, an empty bottle, corked very tight, was sent down 20 fathoms, and it was drawn up still empty. It was then sent down again 35 fathoms, when the weight of the water having forced in the cork, it was drawn up full; the water it contained was immediately tried by the thermometer, and found to be 70, which was six degrees colder than at the surface: the lead and bottle were visible, but not very distinctly so, at the depth of 12 fathoms; but when only 7 fathoms deep they were perfectly seen from the ship. This experiment was thus repeated Sept. 11, when we were in soundings of 18 fathoms. A keg was previously prepared with a valve at each end, one opening inward, the other outward; this was sent to the bottom in expectation that by the valves being both open when going down, and both shut when coming up, it would keep within it the water received at bottom. The upper valve performed its office well, but the under one did not shut quite close, so that much of the water was lost in hauling it up the ship's side. As the water in the keg's passage upwards could not enter at the top, it was concluded that what water remained in it was of that near the ground; and on trying this by the thermometer, it was found to be at 58, which was 12 degrees colder than at the surface.

This last journal was obligingly kept for me by Mr. J. Williams, my fellowpassenger in the London Packet, who made all the experiments with great

exactness.

The chart here given has been constructed with a view to give a more comprehensive idea of the course of the Gulph Stream. Volney very plausibly suggests, that the earth deposited by the Gulph Stream S. E. of Newfoundland, has formed the great banks; and that the accumulation there has given the stream a new or more eastwardly direction. This chart also serves

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to illustrate the long received ideas of the progress of the shoals of fish. May not the glutinous matter seen on the water, and which all persons who have been across the line must have noticed, be another cause of the phenomena of fish shoals? May they not come in search of the food, which the matter seen on the water in such abundance affords? The writer of this note has observed, that on entering the trade winds, the seamen have judged of the change of wind approaching by the direction of the bonetta and other fish, which pass in shoals. in the South Atlantic and South-eastern Seas, in a direction opposite to the wind; and when not opposite to the prevailing wind, they conclude a change. to be at hand from the direction towards which the fish go. The appearance of luminous floating matter at night is often followed by shoals of fish; the spawn or gluten which the writer has had taken up in a bucket, has been often found as large as two inches, diameter, and frequently induced an opinion that it was a species of maritime cocoon or egg of an animal; fragments of irregular shaped gluten have been also often seen. An inquiry into the periodical appearance of these luminous substances on voyages to the southward, and remarks on the usual direction of the shoals of bonetta and other fish, might perhaps lead to very interesting discoveries; it might be assumed as a question worthy of examination, whether the direction of shoals of fish is not towards those points from which periodical winds or currents move the waters; and if the shoals of fish which move from the north poles, and by the British isles the Atlantic, are not led by their instincts in search of these periodical supplies of food; and if the deposits made by the Gulph Stream on the banks of Newfoundland is not the true cause of the great abundance of fish... found there. (Note by an American Gentleman.)

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ON THE PERNICIOUS QUALITY OF LEAD.-COLICA PICTORUM FROM RAINWATER, &c.

DEAR FRIEND,

To B. VAUGHAN, ESQ.

Philadelphia, July 31, 1786.

I recollect that when I had the great pleasure of seeing you at Southampton, now a twelvemonth since, we had some conversation on the bad effects of lead taken inwardly, and that at your request I promised to send you

in writing, a particular account of several facts I then mentioned to you, of which you thought some good use might be made. I now sit down to fulfil that promise.

The first thing I remember of this kind was a general discourse in Boston when I was a boy, of a complaint from North Carolina against New England rum, that it poisoned their people, giving them the dry belly-ache, with a loss of the use of their limbs. The distilleries being examined on the occasion, it was found that several of them used leaden still heads and worms, and the physicians were of opinion that the mischief was occasioned by that use of lead. The legislature of the Massachusetts thereupon passed an act, prohibiting under severe penalties the use of such still heads and worms thereafter. Enclosed I send you a copy of the act, taken from my printed law book.

In 1724, being in London, I went to work in the printing-house of Mr. Palmer, Bartholomew Close, as a compositor. I there found a practice I had never seen before, of drying cases of types (which are wet in distribution) by placing it sloping before the fire. I found this had the additional advantage when the types were not only dried but heated, of being comfortable to the hands working over them in cold weather. I therefore sometimes heated my case when the types did not want drying. But an old workman observing it, advised me not to do so, telling me, I might lose the use of my hands by it, as two of our companions had nearly done; one of whom, that used to earn his guinea a week, could not then make more than ten shillings; and the other, who had the dangles, but seven and sixpence. This, with a kind of obscure pain that I had sometimes felt, as it were in the bones of my hand, when working over the types made very hot, induced me to omit the practice. But talking afterwards with Mr. James, a letter-founder in the same close, and asking him if his people, who worked over the little furnaces of melted metal, were not subject to that disorder; he made light of any danger from the effluvia, but ascribed it to particles of the metal swallowed with their food by slovenly workmen, who went to their meals after handling the metal, without well washing their fingers, so that some of the metalline particles were taken off by their bread and eaten with it. This appeared to have some reason in it. But the pain I had experienced made me still afraid of those effluvia.

Being in Derbyshire at some of the furnaces for smelting of lead ore, I was told that the smoke of those furnaces was pernicious to the neighboring grass and other vegetables. But I do not recollect to have heard any thing of the

effect of such vegetables eaten by animals. It may be well to make the inquiry.

In America, I have often observed that on the roofs of our shingled houses where moss is apt to grow in northern exposures, if there be any thing on the roof painted with white lead, such as balusters, or frames of dormant windows, &c. there is constantly a streak on the shingles from such paint down to the eaves, on which no moss will grow, but the wood remains constantly free from it. We seldom drink rain-water that falls on our houses; and if we did, perhaps the small quantity of lead descending from such paint, might not be sufficient to produce any sensible ill effect on our bodies. But I have been told of a case in Europe, I forget the place, where a whole family was afflicted with what we call the dry belly-ache, or colica pictorum, by drinking rain-water. It was at a country seat, which being situated too high to have the advantage of a well, was supplied with water from a tank, which received the water from the leaded roofs. This had been drank several years without mischief; but some young trees planted near the house, growing up above the roof, and shedding their leaves upon it, it was supposed an acid in those leaves had corroded the lead they covered, and furnished the water of that year with its baneful particles and qualities.

When I was in Paris with Sir John Pringle in 1767, he visited La Charité, a hospital particularly famous for the cure of that malady, and brought from thence a pamphlet containing a list of the names of persons specifying their professions or trades, who had been cured there. I had the curiosity to examine that list, and found that all the patients were of trades that some way or other use or work in lead; such as plumbers, glaziers, painters, &c. excepting only two kinds, stone-cutters, and soldiers. These I could not reconcile to my notion, that lead was the cause of that disorder. But on my mentioning this difficulty to a physician of that hospital, he informed me that the stonecutters are continually using melted lead to fix the ends of iron ballustrades in stone; and that the soldiers had been employed by painters as laborers in grinding of colors.

This, my dear friend, is all I can at present recollect on the subject. You will see by it, that the opinion of this mischievous effect from lead, is at least above sixty years old; and you will observe with concern how long an useful truth may be known, and exist, before it is generally received and practised on. I am ever, yours most affectionately, B. FRANKLIN.

VOL. III.

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