Is it not thus that fire is amaffed and makes the greatest part of the fubftance of combuftible bodies?

Perhaps when this globe was first formed and its original particles took their place at certain distances from the centre in proportion to their greater or lefs gravity, the fluid fire attracted towards that centre might in great part be obliged, as lighteft, to take place above the reft, and thus form the sphere of fire above fuppofed; which would afterwards be continually diminishing by the fubftance it afforded to organized bodies, and the quantity restored to it again by the burning or other feparating of the parts of those bodies?

Is not the natural heat of animals thus produced by feparating in digeftion the parts of food, and fetting their fire at liberty?

Is it not this fphere of fire which kindles the wandering globes that fometimes pafs through it in our course round the fun, have their surface kindled by it, and burst when their included air is greatly rarefied by the heat on their burning furface?

May it not have been from fuch confiderations that the ancient philofophers fuppofed a sphere of fire to exist above the air of our atmosphere?

No. III.

Defcription of the process to be observed in making large Sheets of paper in the Chinese manner, with one Smooth Jurface. Communicated by Dr. B. FRANKLIN.

Read June 25, 1788.

INE

N Europe to have a large furface of paper connected together and smooth on one fide, the following operations are performed.

1. A number of fmall fheets are to be made feparately.

2. These

2. These are to be couched, one by one, between blankets.

3. When a heap is formed it must be put under a strong prefs, to force out the water.

4.

Then the blankets are to be taken away, one by one, and the fheets hung up to dry.

5. When dry they are to be again preffed, or if to be fized, they must be dipped into fize made of warm water, in which glue and allum are diffolved.

6. They must then be preffed again to force out the fuperfluous fize.

7. They must then be hung up a fecond time to dry, which if the air happens to be damp requires fome days. 8. They must then be taken down, laid together, and again preffed.

9. They must be pafted together at their edges.

10. The whole must be glazed by labour, with a flint. In China, if they would make fheets, fuppofe of four and an half ells long and one and an half ell wide, they have two large vats, each five ells long and two ells wide, made of brick, lined with a plafter that holds water. these the stuff is mixed ready to work.

In

Between thefe vats is built a kiln or ftove, with two inclining fides; each fide fomething larger than the sheet of paper; they are covered with a fine flucco that takes a polifh, and are fo contrived as to be well heated by a fmall fire circulating in the walls.

The mould is made with thin but deep fides, that it may be both light and ftiff: It is fufpended at each end with cords that pafs over pullies faftened to the ceiling, their ends connected with a counterpoife nearly equal the weight of the mould.

Two men one at each end of the mould, lifting it out of the water by the help of the counterpoife, turn it and apply it with the ftuff for the sheet, to the fmooth furVOL. III.

B

face

face of the stove, against which they prefs it, to force out great part of the water through the wires. The heat of the wall foon evaporates the reft, and a boy takes off the dried fheet by rolling it up. The fide next the stove receives the even polish of the ftucco, and is thereby better fitted to receive the impreffion of fine prints. If a degree of fizing is required, a decoction of rice is mixed with the ftuff in the vat.

Thus the great fheet is obtained, fmooth and fized, and. a number of the European operations faved.

As the ftove has two polifhed fides, and there are two vats, the fame operation is at the fame time performed by two other men at the other vat; and one fire ferves.

N. IV.

QUERIES and CONJECTURES relating to Magnetism, anl the Theory of the Earth, in a Letter from Dr. B. FRANKLIN, to Mr. BODOIN,

Read Jan. 15, 1790.

DEAR SIR,

I

RECEIVED your favours by Meffrs. Gore, Hilliard and Lee, with whofe converfation I was much pleased, and wished for more of it; but their ftay with us was too fhort. Whenever you recommend any of your friends to me, you oblige me.

I want to know whether your Philofophical Society received the fecond volume of our Tranfactions. I fent it, but never heard of its arriving. If it mifcarried, I will fend another. Has your Society among its books the French Work fur les Arts & les Metiers? It is voluminous,. well executed, and may be useful in our country. I have bequeathed it them in my will; but if they have it already, I will fubftitute fomething else.

Our

Our ancient correfpondence used to have fomething philofophical in it. As you are now more free from public cares, and I expect to be fo in a few months, why may we not refume that kind of correfpondence? Our' much regretted friend Winthrop once made me the compliment, that I was good at ftarting game for philofophers, let me try if I can start a little for you.

Has the question, how came the earth by its magnetism, ever been confidered?

Is it likely that iron ore immediately exifted when this globe was first formed; or may it not rather be supposed a gradual production of time?

If the earth is at prefent magnetical, in virtue of the maffes of iron ore contained in it, might not fome ages pafs before it had magnetic polarity?

Since iron ore may exift without that polarity, and by being placed in certain circumftances may obtain it, from an external cause, is it not poffible that the earth received its magnetifm from fome fuch caufe?

In short, may not a magnetic power exift throughout our fyftem, perhaps through all fyftems, fo that if men could make a voyage in the ftarry regions, a compafs might be of use? And may not fuch univerfal magnetism, with its uniform direction, be ferviceable in keeping the diurnal revolution of a planet more fteady to the fame axis?

Laftly, as the poles of magnets may be changed by the prefence of ftronger magnets, might not, in ancient times, the near paffing of fome large comet of greater magnetic power than this globe of ours have been a means of changing its poles, and thereby wracking and deranging its furface, placing in different regions the effect of centrifugal force, fo as to raise the waters of the fea in fome, while they were depressed in others?

B 2

Let

Let me add another question or two, not relating indeed to magnetism, but, however, to the theory of the earth.

Is not the finding of great quantities of fhells and bones. of animals, (natural to hot climates) in the cold ones of our prefent world, fome proof that its poles have been changed? Is not the fuppofition that the poles have been changed, the eafieft way of accounting for the deluge, by getting rid of the old difficulty how to dispose of its waters after it was over? Since if the poles were again to be changed, and placed in the prefent equator, the fea would fall there about 15 miles in height, and rife as much in the present polar regions; and the effect would be proportionable if the new poles were placed any where between the present and the equator.

Does not the apparent wrack of the furface of this globe, thrown up into long ridges of mountains, with ftrata in various pofitions, make it probable, that its internal mass is a fluid; but a fluid fo denfe as to float the heaviest of our fubftances? Do we know the limit of condenfation air is capable of? Suppofing it to grow denfer within the furface, in the fame proportion nearly as we find it does without, at what depth may it be equal in denfity with gold?

Can we eafily conceive how the ftrata of the earth could have been fo deranged, if it had not been a mere fhell fupported by a heavier fluid? Would not fuch a fuppofed internal fluid globe be immediately fenfible of a change in the fituation of the earth's axis, alter its form, and thereby burst the shell, and throw up parts of it above the reft? As if we would alter the pofition of the fluid contained in the shell of an egg, and place its longest diameter where the shortest now is, the fhell must break; but would be much harder to break if the whole internal fubftance were as folid and hard as the fhell.

Might not a wave by any means raifed in this fuppofed internal ocean of extremely denfe fluid, raife in fome de

gree