There are so many things to be discover'd, whereof a great part, in all likelyhood shall never be known; that they give an opportunity to those who will not encounter with the Thorns and Difficulties of Natural Philosophy, to affect a sort of Discouragement. A great many to vilify this Natural Science, pretend a mighty veneration for the works of Nature, and that they are absolutely incomprehensible. However, Nature is never so admirable, nor so admir'd as when known. True it is, that what is known is inconsiderable in comparison of what is not yet known. Nay, Sometimes what is not known, is exactly what seems shou'd be the soonest known. As for instance, it is not at least certainly known, why a Stone thrown up into the Air falls down again; but we certainly know the cause of the Rainbow, why it doth not exceed a certain height; why its breadth is always the same; why when there are two Rainbows at the same time, the Colours of the one are overset with reference to the Colours of the other; and yet the fall of a Stone in the Air appears a more simple Phænomenon, than the Rainbow. But in a word, altho' we do not know every thing, we are not neither ignorant of every thing. And altho' we are ignorant of the most simple Events, yet we have a knowledge of what seems the most Complex. So that if we have on the one hand reason to fear, lest our Vanity shou'd flatter us with the hopes of attaining to the knowledge of things above our reach; on the other we ought to dread, lest our Slothfulness should also flatter us that we are condemn'd to a greater degree of Ignorance than really we are.
People may think that the Sciences do not begin to exert themselves, either because they cou'd be but imperfect among the Ancients; or because we have almost lost the Footsteps of them during the gloomy Darkness of Barbarity; or because a better method hath been taken about 100 Years ago. Was the Progress Historically examin'd, they have already made in so short a time, notwithstanding the strong, but false Prejudices they had long to encounter with, even sometimes the foreign Obstacles they have met with from Authority and Power; the want of Zeal for Sciences so remote from common use, those few who apply'd themselves to this Work, and the weak Motives which engag'd them in it; a Man would wonder at the Greatness and Rapidity of the Progress of the Sciences, and even we might observe some new ones to start out of nothing, and perhaps be tempted to have too great hopes of future Improvements.
The greater reason we have of future Success, the greater we have to look upon the Sciences as in their Cradles, at least Natural Philosophy. And therefore the Academy is only now employ'd to make an ample Provision of Observations, and Facts well attested, which may one day be the foundation of a System. For before the Systematical Natural Philosophy can raise solid Edifices; Experimental Natural Philosophy must be in a condition to supply it with good Materials.
None but Societies, of those too countenanc'd and encourag'd by the Prince, can successfully make and prepare this Collection of Materials. All the Learning, Care, Life and Wealth of one Private Man can never answer this Design. There are too many different Experiments to be made, which are to be too much vary'd, and a long time prosecuted with the same Temper and Mind. The Cause of the least Effect is so wrap'd up, that unless you very carefully open all the various Foldings, you cannot come at it.
Hitherto the Academy of Sciences hath consider'd Nature but by parcels: They have fix'd upon no general System, for fear of falling into the inconveniency of hasty Systems, which are very grateful to the impatience of Humane Understanding; and being once settled, are Obstacles to what Truths are afterwards discover'd. This day we are sure of a Fact, to morrow we shall be sure of another that hath no relation with the former. However some Conjectures are ventur'd at upon Causes; but they are only Conjectures. So that this Collection, which the Academy gives to the Publick, is compos'd of separate Fragments, independant of one another; whereof every one who is the Author, warrants the Facts and Experiments; and whose Arguments are approv'd by the Academy, but with Restrictions becoming Wise and Wary Scepticks.
Time perhaps will come, when these scatter'd Fragments shall be united into one regular Body; and if they be such as they are wish'd, they may of themselves Unite. A great many Truths, when their Numbers is considerable, shew so near a Relation to, and so mutual a Dependance upon one another, that it seems, that notwithstanding their violent Separation, they have a natural Tendency to be re-united.
A
TABLE
OF THE
Discourses contain'd in this Volume.
| PAGE | |
| An Estimate of the Quantity of Vapours raised out of the Sea, as derived from Experiment: Together with an Account of the Circulation of the wat'ry Vapours of the Sea, and of the Cause of Springs. Presented to the Royal Society by Mr. E. Halley, F. R. S. | [1] |
| The True Theory of the Tides, extracted from that admired Treatise of Mr. Isaac Newton, Intituled Philosophiæ Naturalis Principia Mathematica; being a Discourse presented with that Book to the late King James, by Mr. E. Halley. | [13] |
| A Theory of the Variation of the Magnetical Compass, by Mr. E. Halley. | [27] |
| An Account of the Cause of the Change of the Variation of the Magnetical Needle, with an Hypothesis of the Structure of the Internal Parts of the Earth; as it was presented to the Royal Society in one of their late Meetings, by Mr. E. Halley. | [43] |
| An Historical Account of the Trade-Winds and Monsoons, observable in the Seas between and near the Tropicks; with an Attempt to assign the Physical Cause of the said Winds, by Mr. E. Halley. | [61] |
| A Discourse of the Rule of the Decrease of the Heighth of the Mercury in the Barometer, according as Places are elevated above the Surface of the Earth; with an Attempt to discover the true Reason of the rising and falling of the Mercury, upon Change of Weather, by Mr. E. Halley. | [81] |
| A Letter from Mr. Isaac Newton, while Professor of the Mathematicks in the University of Cambridge; containing his new Theory about Light and Colours: Sent from Cambridge, Feb. 6. 1671/2. in order to be communicated to the Royal Society. | [97] |
| A farther Explanation of the same Theory. | [114] |
| A Demonstration concerning the Motion of Light, communicated from Paris. | [118] |
| An Introductory Essay to the Doctrine of Sounds, containing some Proposals for the Improvement of Acousticks; as it was presented to the Dublin Society, by the Right Reverend Father in God Narcissus, Lord Bishop of Ferns and Leighlin. | [121] |
| A Discourse concerning the Modern Theory of Generation, by Dr. Geo. Garden, of Aberdeen, being part of a Letter to Dr. William Musgrave, L. L. D. Reg. Soc. S. and by him communicated to the Royal Society. | [142] |
| A short Discourse concerning Concoction Read at a Meeting of the Royal Society, by Clopton Havers, M. D. Fellow of the Royal Society. | [153] |
| A Discourse concerning some Influence of Respiration on the Motion of the Heart hitherto unobserved. By J. Drake, M. D. F. R. S. | [171] |
| Some Thoughts and Experiments concerning Vegetation. By John Woodward, M. D. of the College of Physicians and Royal Society, and Professor of Physick in Gresham-College. | [203] |
| An Account of the Measure of Gold upon Gilt Wire; together with a Demonstration of the exceeding Minuteness of the Atoms, or constituent Parts of Gold; as it was read before the Royal Society, by Mr. E. Halley. | [243] |
| An Account of the several Species of Infinite Quantity, and of the Proportions they bear one to the other; as it was read before the Royal Society, by E. Halley. | [246] |
| An Account of Dr. Robert Hook's Invention of the Marine Barometer, with it's Description and Uses. Published by Order of the Royal Society by Mr. E. Halley. | [250] |
| A Discourse concerning the Proportional Heat of the Sun in all Latitudes; with the Method of collecting the same, as it was read before the Royal Society in one of their late Meetings, by Mr. E. Halley. | [256] |
| Concerning the Distance of the Fixed Stars, bythe Honourable Fran. Roberts, Esq; F. R. S. | [265] |
| Mr. Isaac Newton's Theory of the Moon. | [268] |
| An estimate of the Degrees of the Mortality of Mankind, drawn from Curious Tables of Births and Funerals at the City of Breslaw; with an Attempt to ascertain the Price of Annuities upon Lives, by Mr. E. Halley. | [280] |
| A Discourse concerning Gravity, and its Properties, wherein the Descent of Heavy Bodies, and the Motion of Projects is briefly, but fully handled: Together with the Solution of a Problem of great Use in Gunnery, by Mr. E. Halley. | [302] |
| A Proposition of General Use in the Art of Gunnery, shewing the Rule of laying a Mortar to pass, in order to strike any Object above or below the Horizon, by Mr. E. Halley. | [326] |
| A Discourse concerning the Measure of the Air's Resistance to Bodies moved in it. By the Learned John Wallis, S. T. D. and F. R. S. | [332] |
| An Instance of the Excellency of the Modern Algebra, in the Resolution of the Problem of finding the Foci of Optick Glasses universally. By Mr. E. Halley, S. R. S. | [348] |
| Appendix | |
| An Analytical Resolution of certain Equations of the 3d, 5th, 7th, 9th Powers, and so on ad Infinitum, in finite Terms, after the manner of Cardan's Rules for Cubicks. By Mr. A. Moivre, F. R. S. | [365] |
| A Discourse concerning the Action of the Sun and Moon on Animal Bodies; and the Influence which this may have in many Diseases. By Richard Mead, M. D. F. R. S. | [371] |