Part 1
TRANSCRIBER'S NOTE
This is Volume 2 of a 3-volume set. The other two volumes are also accessible in Project Gutenberg using https://www.gutenberg.org/ebooks/48136 and https://www.gutenberg.org/ebooks/48138.
Italic text is denoted by _underscores_.
Obvious typographical errors and punctuation errors have been corrected after careful comparison with other occurrences within the text and consultation of external sources.
Several pages of the book contain a description and examples of a modified alphabet proposed by B.F. There are six new characters, which are denoted by the Unicode characters below (these are similar to, but not a precise rendering of the original printed characters). ϖ for the 'o' sound as in (John, folly, ball) 0x3d6 ų for the 'u' sound as in (umbrage, unto, er) 0x173 Ի for the 'sh' sound as in (ship, wish) 0x53b ŋ for the 'ng' sound as in (ing, repeating, among) 0x14b ɧ for the 'th' sound as in (think, width) 0x267 ƕ for the 'th' sound as in (thy, weather) 0x195
More detail can be found at the end of the book.
The WORKS Of BENJAMIN FRANKLIN, L.L.D.
VOL. 2.
PRINTED,
for Longman, Hurst, Rees, & Orme, Paternoster Row, London.
THE COMPLETE WORKS, IN PHILOSOPHY, POLITICS, AND MORALS, OF THE LATE DR. BENJAMIN FRANKLIN, NOW FIRST COLLECTED AND ARRANGED: WITH MEMOIRS OF HIS EARLY LIFE, WRITTEN BY HIMSELF.
IN THREE VOLUMES.
VOL. II.
London:
PRINTED FOR J. JOHNSON, ST. PAUL'S CHURCH-YARD; AND LONGMAN, HURST, REES AND ORME, PATERNOSTER-ROW.
1806.
J. CUNDEE, PRINTER LONDON
CONTENTS.
VOL. II.
LETTERS AND PAPERS ON PHILOSOPHICAL SUBJECTS.
Physical and meteorological observations, conjectures and suppositions 1
On water-spouts 11
The same subject continued 13
Water-spouts and whirlwinds compared 19
Description of a water-spout at Antigua 34
Shooting stars 36
Water-spouts and whirlwinds 37
Observations on the meteorological paper; by a gentleman in Connecticut 45
Observations in answer to the foregoing, by B. Franklin 49
Observations on the meteorological paper; sent by a gentleman in New York to B. Franklin 51
Answer to the foregoing observations, by B. Franklin 55
Gentleman of New York in reply 58
Account of a whirlwind at Maryland 61
On the north east storms in North America 63
Meteorological imaginations and conjectures 66
Suppositions and conjectures towards forming an hypothesis, for the explanation of the aurora borealis 69
On cold produced by evaporation 75
On the same subject 83
Concerning the light in sea-water 88
On the saltness of sea-water 91
On the effect of air on the barometer, and the benefits derived from the study of insects 92
On the Bristol waters, and the tide in rivers 95
On the same subject 102
Salt-water rendered fresh by distillation.--Method of relieving thirst by sea-water 103
Tendency of rivers to the sea.--Effect of the sun's rays on cloth of different colours 105
On the vis inertiæ of matter 110
On the different strata of the earth 116
On the theory of the earth 117
New and curious theory of light and heat 122
Queries and conjectures relating to magnetism and the theory of the earth 125
On the nature of sea coal 125
Effect of vegetation on noxious air 129
On the inflammability of the surface of certain rivers in America 130
On the different quantities of rain which fall at different heights over the same ground 133
Slowly sensible hygrometer proposed, for certain purposes 135
Curious instance of the effect of oil on water 142
Letters on the stilling of waves by means of oil 144
Extract of a letter from Mr. Tengnagel to Count Bentinck, dated at Batavia, the 5th of January, 1770 154
On the difference of navigation in shoal and deep water 158
Sundry maritime observations 162
Remarks upon the navigation from Newfoundland to New-York, in order to avoid the Gulph Stream on one hand, and on the other the shoals that lie to the southward of Nantucket and of St. George's Banks 197
Observations of the warmth of the sea-water, &c. by Fahrenheit's Thermometer, in crossing the Gulph Stream; with other remarks made on board the Pensylvania packet, Capt. Osborne, bound from London to Philadelphia, in April and May, 1775 199
Observations of the warmth of the sea-water, &c. by Fahrenheit's thermometer; with other remarks made on board the Reprisal, Capt. Wycks, bound from Philadelphia to France, in October and November, 1776 200
A journal of a voyage from the Channel between France and England towards America 202
On the art of swimming 206
On the same subject, in answer to some enquiries of M. Dubourg 210
On the free use of air 213
On the causes of colds 214
Dr. Stark, and Dr. Letsom 215
Number of deaths in Philadelphia by inoculation ibid
Answer to the preceding 217
On the effects of lead upon the human constitution 219
Observations on the prevailing doctrines of life and death 222
An account of the new-invented Pensylvanian fire-places 225
On the causes and cure of smoky chimneys 256
Description of a new stove for burning of pitcoal, and consuming all its smoke 296
Method of contracting chimneys.--Modesty in disputation 317
Covering houses with copper 318
On the same subject 320
Paper referred to in the preceding letter 322
Magical square of squares 324
Magical circle 328
New musical instrument composed of glasses 330
Best mediums for conveying sound 335
On the harmony and melody of the old Scotch tunes 338
On the defects of modern music 343
Description of the process to be observed in making large sheets of paper in the Chinese manner, with one smooth surface 349
On modern innovations in the English language and in printing 351
A scheme for a new alphabet and reformed mode of spelling; with remarks and examples concerning the same; and an enquiry into its uses, in a correspondence between Miss S---- and Dr. Franklin, written in the characters of the alphabet 357
Rules for a club formerly established in Philadelphia 366
Questions discussed by the Junto forming the preceding club 369
Sketch of an English school; for the consideration of the trustees of the Philadelphia Academy 370
Advice to youth in reading 378
PAPERS ON SUBJECTS OF GENERAL POLITICS.
Observations concerning the increase of mankind, peopling of countries, &c 383
Remarks on some of the foregoing observations, showing particularly the effect which manners have on population 392
Plan by Messieurs Franklin and Dalrymple, for benefiting distant unprovided countries 403
Concerning the provision made in China against famine 407
Positions to be examined, concerning national wealth 408
Political fragments, supposed either to be written by Dr. Franklin, or to contain sentiments nearly allied to his own 411
On the price of corn, and management of the poor 418
On luxury, idleness, and industry 424
On smuggling, and its various species 430
Observations on war 435
Notes copied from Dr. Franklin's writing in pencil in the margin of Judge Foster's celebrated argument in favour of the impressing of seamen 437
On the criminal laws, and the practice of privateering 441
A parable against persecution, in imitation of scripture language 450
A letter concerning persecution in former ages, the maintenance of the clergy, American bishops, and the state of toleration in Old England and New England compared 452
On the slave trade 459
Account of the highest court of judicature in Pensylvania, viz. The court of the press 463
LIST OF THE PLATES
PLATE V. Water-Spouts facing page 16
PLATE VI. Maritime Observations 163
PLATE VII. A Chart of the Gulph Stream 197
PLATE VIII. Pensylvania Fire-Place 235
PLATE VIII*. Profile of the Pensylvania Chimnie 238
PLATE IX. Remedies for Smoky Chimnies 269
PLATE X. Stove for Burning Pit-Coal 297
PLATE XI. A Magic Square of Squares 327
PLATE XII. A Magic Circle of Circles 328
_ERRATA._
_Page._ _Line._
117 penult. for preceding day, read the preceding day. 254 17: for the annexed cut, read Plate VIII. 276 11: for Plate I, read Plate IX. 293 23: for Fig. 13, read Fig. 10. 318 9: for descent, read decent. 326 5: for Plate XI, read Plate V. Fig. 3.
LETTERS AND PAPERS
ON
_PHILOSOPHICAL SUBJECTS._
_LETTERS AND PAPERS_
ON
PHILOSOPHICAL SUBJECTS.
_Physical and Meteorological Observations, Conjectures and Suppositions._
Read at the Royal Society, June 3, 1756.
The particles of air are kept at a distance from each other by their mutual repulsion.
Every three particles, mutually and equally repelling each other, must form an equilateral triangle.
All the particles of air gravitate towards the earth, which gravitation compresses them, and shortens the sides of the triangles, otherwise their mutual repellency would force them to greater distances from each other.
Whatever particles of other matter (not endued with that repellency) are supported in air, must adhere to the particles of air, and be supported by them; for in the vacancies there is nothing they can rest on.
Air and water mutually attract each other. Hence water will dissolve in air, as salt in water.
The specific gravity of matter is not altered by dividing the matter, though the superficies be increased. Sixteen leaden bullets, of an ounce each, weigh as much in water as one of a pound, whose superficies is less.
Therefore the supporting of salt in water is not owing to its superficies being increased.
A lump of salt, though laid at rest at the bottom of a vessel of water, will dissolve therein, and its parts move every way, till equally diffused in the water; therefore there is a mutual attraction between water and salt. Every particle of water assumes as many of salt as can adhere to it; when more is added, it precipitates, and will not remain suspended.
Water, in the same manner, will dissolve in air, every particle of air assuming one or more particles of water. When too much is added, it precipitates in rain.
But there not being the same contiguity between the particles of air as of water, the solution of water in air is not carried on without a motion of the air, so as to cause a fresh accession of dry particles.
Part of a fluid, having more of what it dissolves, will communicate to other parts that have less. Thus very salt water, coming in contact with fresh, communicates its saltness till all is equal, and the sooner if there is a little motion of the water.
Even earth will dissolve, or mix with air. A stroke of a horse's hoof on the ground, in a hot dusty road, will raise a cloud of dust, that shall, if there be a light breeze, expand every way, till, perhaps, near as big as a common house. It is not by mechanical motion communicated to the particles of dust by the hoof, that they fly so far, nor by the wind, that they spread so wide: but the air near the ground, more heated by the hot dust struck into it, is rarefied and rises, and in rising mixes with the cooler air, and communicates of its dust to it, and it is at length so diffused as to become invisible. Quantities of dust are thus carried up in dry seasons: showers wash it from the air, and bring it down again. For water attracting it stronger, it quits the air, and adheres to the water.
Air, suffering continual changes in the degrees of its heat, from various causes and circumstances, and, consequently, changes in its specific gravity, must therefore be in continual motion.
A small quantity of fire mixed with water (or degree of heat therein) so weakens the cohesion of its particles, that those on the surface easily quit it, and adhere to the particles of air.
A greater degree of heat is required to break the cohesion between water and air.
Air moderately heated will support a greater quantity of water invisibly than cold air; for its particles being by heat repelled to a greater distance from each other, thereby more easily keep the particles of water that are annexed to them from running into cohesions that would obstruct, refract, or reflect the light.
Hence when we breathe in warm air, though the same quantity of moisture may be taken up from the lungs, as when we breathe in cold air, yet that moisture is not so visible.
Water being extremely heated, _i.e._ to the degree of boiling, its particles in quitting it so repel each other, as to take up vastly more space than before, and by that repellency support themselves, expelling the air from the space they occupy. That degree of heat being lessened, they again mutually attract, and having no air-particles mixed to adhere to, by which they might be supported and kept at a distance, they instantly fall, coalesce, and become water again.
The water commonly diffused in our atmosphere never receives such a degree of heat from the sun, or other cause, as water has when boiling; it is not, therefore, supported by such heat, but by adhering to air.
Water being dissolved in, and adhering to air, that air will not readily take up oil, because of the mutual repellency between water and oil.
Hence cold oils evaporate but slowly, the air having generally a quantity of dissolved water.
Oil being heated extremely, the air that approaches its surface will be also heated extremely; the water then quitting it, it will attract and carry off oil, which can now adhere to it. Hence the quick evaporation of oil heated to a great degree.
Oil being dissolved in air, the particles to which it adheres will not take up water.
Hence the suffocating nature of air impregnated with burnt grease, as from snuffs of candles and the like. A certain quantity of moisture should be every moment discharged and taken away from the lungs; air that has been frequently breathed, is already overloaded, and, for that reason, can take no more, so will not answer the end. Greasy air refuses to touch it. In both cases suffocation for want of the discharge.
Air will attract and support many other substances.
A particle of air loaded with adhering water, or any other matter, is heavier than before and would descend.
The atmosphere supposed at rest, a loaded descending particle must act with a force on the particles it passes between, or meets with, sufficient to overcome, in some degree, their mutual repellency, and push them nearer to each other.
Thus, supposing the particles A B C D, and the other near them, to be at the distance caused by their mutual repellency (confined by their common gravity) if A would descend to E, it must pass between B and C; when it comes between B and C, it will be nearer to them than before, and must either have pushed them nearer to F and G, contrary to their mutual repellency, or pass through by a force exceeding its repellency with them. It then approaches D, and, to move it out of the way, must act on it with a force sufficient to overcome its repellency with the two next lower particles, by which it is kept in its present situation.
Every particle of air, therefore, will bear any load inferior to the force of these repulsions.
Hence the support of fogs, mists, clouds.
Very warm air, clear, though supporting a very great quantity of moisture, will grow turbid and cloudy on the mixture of a colder air, as foggy turbid air will grow clear by warming.
Thus the sun shining on a morning fog, dissipates it; clouds are seen to waste in a sun-shiny day.
But cold condenses and renders visible the vapour; a tankard or decanter filled with cold water will condense the moisture of warm clear air on its outside, where it becomes visible as dew, coalesces into drops, descends in little streams.
The sun heats the air of our atmosphere most near the surface of the earth; for there, besides the direct rays, there are many reflections. Moreover, the earth itself being heated, communicates of its heat to the neighbouring air.
The higher regions, having only the direct rays of the sun passing through them, are comparatively very cold. Hence the cold air on the tops of mountains, and snow on some of them all the year, even in the torrid zone. Hence hail in summer.
If the atmosphere were, all of it (both above and below) always of the same temper as to cold or heat, then the upper air would always be _rarer_ than the lower, because the pressure on it is less; consequently lighter, and therefore would keep its place.
But the upper air may be more condensed by cold, than the lower air by pressure; the lower more expanded by heat, than the upper for want of pressure. In such case the upper air will become the heavier, the lower the lighter.
The lower region of air being heated and expanded heaves up, and supports for some time the colder heavier air above, and will continue to support it while the equilibrium is kept. Thus water is supported in an inverted open glass, while the equilibrium is maintained by the equal pressure upwards of the air below; but the equilibrium by any means breaking, the water descends on the heavier side, and the air rises into its place.
The lifted heavy cold air over a heated country, becoming by any means unequally supported, or unequal in its weight, the heaviest part descends first, and the rest follows impetuously. Hence gusts after heats, and hurricanes in hot climates. Hence the air of gusts and hurricanes cold, though in hot climes and seasons; it coming from above.
The cold air descending from above, as it penetrates our warm region full of watry particles, condenses them, renders them visible, forms a cloud thick and dark, overcasting sometimes, at once, large and extensive; sometimes, when seen at a distance, small at first, gradually increasing; the cold edge, or surface of the cloud, condensing the vapours next it, which form smaller clouds that join it, increase its bulk, it descends with the wind and its acquired weight, draws nearer the earth, grows denser with continual additions of water, and discharges heavy showers.
Small black clouds thus appearing in a clear sky, in hot climates, portend storms, and warn seamen to hand their sails.
The earth, turning on its axis in about twenty-four hours, the equatorial parts must move about fifteen miles in each minute; in northern and southern latitudes this motion is gradually less to the poles, and there nothing.
If there was a general calm over the face of the globe, it must be by the air's moving in every part as fast as the earth or sea it covers.
He that sails, or rides, has insensibly the same degree of motion as the ship or coach with which he is connected. If the ship strikes the shore, or the coach stops suddenly, the motion continuing in the man, he is thrown forward. If a man were to jump from the land into a swift sailing ship, he would be thrown backward (or towards the stern) not having at first the motion of the ship.
He that travels by sea or land, towards the equinoctial, gradually acquires motion; from it, loses.
But if a man were taken up from latitude 40 (where suppose the earth's surface to move twelve miles per minute) and immediately set down at the equinoctial, without changing the motion he had, his heels would be struck up, he would fall westward. If taken up from the equinoctial, and set down in latitude 40, he would fall eastward.
The air under the equator, and between the tropics, being constantly heated and rarefied by the sun, rises. Its place is supplied by air from northern and southern latitudes, which coming from parts where the earth and air had less motion, and not suddenly acquiring the quicker motion of the equatorial earth, appears an east wind blowing westward; the earth moving from west to east, and slipping under the air[1].
Thus, when we ride in a calm, it seems a wind against us: if we ride with the wind, and faster, even that will seem a small wind against us.
The air rarefied between the tropics, and rising, must flow in the higher region north and south. Before it rose, it had acquired the greatest motion the earth's rotation could give it. It retains some degree of this motion, and descending in higher latitudes, where the earth's motion is less, will appear a westerly wind, yet tending towards the equatorial parts, to supply the vacancy occasioned by the air of the lower regions flowing thitherwards.
Hence our general cold winds are about north west, our summer cold gusts the same.