Sciothericum telescopicum, or, A new contrivance of adapting a telescope to an horizontal dial for observing the moment of time by day or night useful in all astronomical observations, and for regulating and adjusting curious pendulum-watches and other time-keepers, with proper tables requisite thereto / by William Molyneux ...

TO HIS EXCELLENCY Henry Earl of Clarendon, LORD Lieutenant General, AND GENERAL GOVERNOUR OF His MAJESTIES Kingdom OF IRELAND.

THe great Honour Your Excellency was pleased to shew Our Society in accepting Our Congratu∣lation at Your happy Arrival and Settlement in the Go∣vernment of this Kingdom, and in giving us Your In∣couragement in prosecuting our Philosophical Designs,

does necessarily require from us all possible Returns of Gratitude. And though what I now Present Your Excellency may seem unfit to begin withal, yet I could not omit this opportunity of expressing to Your Lord∣ship the deep sense I have of Your Favours to us, and to Philosophy. And certainly, my Lord, True Phi∣losophy does highly deserve Encouragement from the Wise, the Great, and Powerful; the most Learned Universities have at all times made Natural Philo∣sophy and Mathematicks a great Branch of their Literature, and we see how universaly Academick Knowledge has been approved of by the great En∣couragement and large Priviledges the Schools have received from our Wisest Princes, and by the general agreement of the most sober and considerate men, in sending their Youth to receive their Education there∣in. This shews how universaly Philosophick Learn∣ing has been approved; and the only Question that can be raised at present is, Whether the Natural Philo∣sophy formerly professed in the Schools, or that which is at present prosecuted by the Societies lately Institu∣ted in several the most noted parts of Europe, be the True Philosophy, or method of Investigating Na∣ture. But surely this will be no longer a doubt, when we consider how unsatisfactory were the ancient No∣tions of Philosophy, which then consisted rather in Disputes, and Verbose empty Stuff, than in any Cu∣rious Discovery of Natures Actions. If a man could prove Pro and Con, whatever was proposed, and main∣tain

this Dispute for two or three hours by vain Di∣stinctions and idle Evasions, he presently gain'd the Name of a Philosopher, tho all the while he had no manner of Notions in his Brain answerable to those senseless words he threw out. I would fain know, what Notion any man has of Light upon pronouncing the definition of it, Actus Perspicui quatenus Perspi∣cuum, does he hereby in the least understand any of the properties of Light, or how 'tis affected by Refracti∣on or Reflection? or does this Definition lead him to improve Light for the advancement and help of our senses, or other advantage of mankind? And now, my Lord, if this kind of Philosophy which formerly fill'd our Schools were look'd upon as deserving the Fa∣vour of the Great, how much more shall the present useful Enquiries of the Ingenious deserve Incou∣ragement? But that this may be made a little more evident (though I am perswaded 'tis sufficiently manifest already to Your Excellencys Discerning Judgment) I shall crave leave to be more particular in this matter; And I shall begin with one of the most Considerable and Ʋniversal Concerns of Mans Life, I mean Naviga∣tion, wherein the Philosophy of the Moderns has been very much Exercised; The Magnet by its Ca∣prichious Variations is at present in several parts of the World rendred almost useless; but diligent search is daily made after its Vagarys, that we may not be depri∣ved of the unspeakable benefit of one of the most surpri∣sing Phenomenas in Nature. Certainly men might

have Disputed from Age to Age of Sympathy, Anti∣pathy, and the Occult Qualities of the Loadstone, before they should ever arrive to the Knowledge or Re∣ctification of one of these Exorbitances, which dili∣gent Experimental Philosophy presently discovers, and further Experiments may hope to Rectify. In re∣lation likewise no Navigation are all the Enquiries into the Theory of the Tides, and the Moons motion, all the Endeavours for the Longitude, and the Diligence used to Rectify Astronomy. The Philosophy of Hy∣draulicks and Hydrostaticks tends to the great E∣molument and Pleasure of Mankind, no place being habitable without Water, and Curious Fountains adorn the Gardens and Houses of the Greatest Princes. Agri∣culture, and the Philosophy relating to Earth and Vegitation, is of universal extent over the face of the World; and how mightily it has been lately prosecuted, is evident from the Incomparable Works of Mr. Evelyn and others. By the Doctrine of Light, and the Pro∣perties thereof, our most Noble Sense has been Improved to an Acuteness some thousands of degrees beyond its na∣tural Abilities; and the Telescope and Microscope discover to us new Worlds and Animals, extending the Creation farther than 'twas possible for the Ancients to imagine. There is no state of Life that is not con∣cern'd in Meteorology, or the Philosophy of the Weather. And all that have heard of the late contri∣ved Baroscopes, Hygroscopes, Thermoters, &c. may plainly perceive what Endeavours have been made towards it, and their success.

I might proceed on, and fill a Volume with Instances to Your Excellency of the usefulness of an Active Ex∣perimental Philosophy; but I stop my hand, and shall only declare in short, that from this alone we are to expect advancements in the most important concerns of humane life; the Virtues of Animals, Plants and Minerals for the health of mans Body, Architecture Civil and Military for the pleasure and security of his life; all kind of Machines and Movements for the increase and due application of his strength, proceed from this kind of Phi∣losophy, which consists in Actions, not in Words, and prosecutes and sometimes Improves Nature by the same steps that she her self acts by. And indeed, my Lord, if we consider Nature as an Active Principle, we must needs acknowledge that she is to be prosecuted by Action, and not by Verbose Disputes; There is nothing that the mind of man will not find something to say for or a∣gainst all day long; and therefore of the School-Disputes there is no end; but Experiment is matter of Fact, and strikes the Senses so forcibly, that there is no opposing it. Who is it that will now question the force of Gun-pow∣der, or whether the Mercury rise and fall in the Ba∣roscope at fair or foul Weather?

'Tis therefore this Philosophy (may it please Your Excellency) that deserves Favour and In∣couragement from the Powerful and Wise; and as God has made all things in number, measure, and weight, that Learning which teaches us the affections

of number and measure, as being the Foundation on which true Philosophy is to be superstructed, is chiefly to be respected. There is no part of Philosophy where∣in the Mathematicks are not deeply ingredient, and on them depend the Arts of War as the Delights of Peace, and even Sacred Theology it self is in a great measure beholding hereto for its help, if we consider how far the Chronology of the Holy Scriptures is help'd out by Astronomy, and the Doctrine of Eclipses.

And as I have presumed to detain Your Excellency thus long, in declaring how true Philosophy deserves Your Protection, so give me leave to add one word more in declaring how Your Excellency deserves the Tu∣telage of true Philosophy. Your Illustrious Father, of Happy Memory, was no unactive Speculative Philo∣sopher, but was zealous and forward in promoting the Noble Design of the Royal Society, as appears to his immortal Praise in their Incomparable History, and by their Electing him, and his willing Complyance to be their Protector. Neither did he only countenance Phi∣losophy by his Authority and Favour, but actually drew the Sword in its defence against the great Sea Mon∣ster that would have destroy'd the Virgin; as is mani∣fest from his Learned and Ingenious Treatise against the Leviathan. All the World that know Your Lord∣ship, must acknowledge that this and other his extraor∣dinary Virtues are entail'd on Your Excellency, who has not buried the Talent in a Napkin, but improved

it to an high degree. Your Excellency has Honoured the Royal Society by being one of their Number, and their last years Council was compleated by Your be∣ing one of them. So that upon all occasions Your Ex∣cellency has shewn Your Self a zealous Patron of Learning and Ingenuity; and though I dare not on either score challenge Your Excellency's Protection of what I here present You, for I am afraid to trust my own Judgment in my own Concern; yet I will presume to implore Your Favour towards it as 'tis new, and not disliked by some Ingenious Men to whom I have shewn it. Whether it may deserve Your Excellency's Coun∣tenance for its Ʋse and Advantage, I leave to Your own discerning Thought, after Your Lordship is pleased to consider what I offer in the First and Second Chapters. However, this I will venture to assert before-hand, that as Clocks or Time-keepers by Wheels and Weights have been an ancient Invention, (if we believe Severinus Boethius to be the first Author of them, 'tis above 1100 years ago) yet in these later days they have received a most high advancement (to the immortal glory of M^nsr. Hugens) by the addition of a plain and simple Swag or Pendulum; since the days of Hezekiah, wherein we first find Dials mentioned, I have not heard of a more plain and easy addition for the advancement of Dials, and in∣larging and ascertaining their Ʋse, than what I here pro∣pose. And though I shall not be so vain, as to expect its sudden propagation, or any great Glory from the Contri∣vance;

yet if I can be so happy as thereby to Divert and Please Your Excellency, and in some measure to pur∣chase Your Favour, 'tis the highest Ambition of

Your Excellencies Most Obedient Humble Servant, WILL. MOLYNEƲX.

Dublin, April 17. 1686.