Volume 1

An introduction to a general system of hydrostaticks and hydraulicks, philosophical and practical : Wherein the most reasonable and advantageous methods of raising and conducting water, for the watering noblemens and gentlemens seats, buildings, gardens, &c., are carefully (and in a manner not yet publish'd in any language) laid down ... / By Stephen Switzer.

  • Switzer, Stephen, 1682?-1745.
Date:
1729
Catalogue details

Licence: Public Domain Mark

Credit: An introduction to a general system of hydrostaticks and hydraulicks, philosophical and practical : Wherein the most reasonable and advantageous methods of raising and conducting water, for the watering noblemens and gentlemens seats, buildings, gardens, &c., are carefully (and in a manner not yet publish'd in any language) laid down ... / By Stephen Switzer. Source: Wellcome Collection.

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    defcend to E, and then the Air prefixing on one Side at E, and on the other at C, joint¬ ly fuftain the Water in the Bottle from E and C, up to A and H, and it wou’d even fudain it, though the Height C H were of 30 Feet, provided the End of the Tube were below the Bottom of the Hole C ; but when the Tube defcends no lower than L, then the Water from L to E, join’d to the Weight of the Air which preifes upon L, will overpoife the Air at C, and the Water will go out through the Hole C, whild the Air defcending from D to L, and entering Drop by Drop into the Water through the open End L, rifes above the Surface of the Water which is below the Neck of the Bottle ; but if you incline the Bottle in fuch Manner that the Point L and the Middle of the Aperture C may be in the fame horizontal Line, you will fee half a Drop of the Air get below the Point L, but not feparate fronv the red, unlefs you raife the End L a little higher. When you have let fome Air into the Bottle, fo that the Surface of the Water is at N O, and dilate that Air by heating it with your Hand, you will force out fome Drops of Water at C, though the End of the Tube be below this Hole, and the Water will defcend as to p q, but if you let the Air grow cold again/you will fee for fome time Bubbles of Air enter in at G ; becaufe the Air which had defeended as far as P Q^, contrasting it felf within the Space which it took up at fir ft from N O at A H, and there being no Water to fill up the Space NO P Qj the Air mufl .come in from without, through the Hole C. Water has no fenfible Eladicity, and ; makes an Equilibrium with other Bodies only by its Weight or Impulfe: The fird Equilibrium that is remarkable in Water, with refpedt to Air, is, that being reduc’d to very fmall Particles, it becomes lighter than Air, and rifes in a Vapour, as was before obferved. We can’t tell how fmall fuch-a Particle of Water mud.be to make ail Equilibrium, with the Air near the Earth, becaufe thofe Particles, which are a little lighter or a little heavier than Air, are in- vifible when they are feparate from each other. ’Tis very difficult likewife to find out the Reafon of their Rife, for it can’t be that they are mix’d with Air, becaufe they would dill weigh more than pure Air; ’tis not by Reafon of Heat, becaufe we fee Va¬ pours arife from very cold Water • ’tis probable then that in the Air there are’vcry fine Pores, void of all heavy Matter, into which thefe fine Particles of Water may infinuate themfelves, and rife therein, and into which thegroffer Particles can’t enter. These fmall Particles make an Equili¬ brium with the Air at about a League or two Leagues Didance from, the Earth* where they remain a long Time fufpended^ till many of them being join’d together they become heavier ; and when the Air is very much rarefied, they fall to the Earth. This is further illudrated by an Experi¬ ment in the Air-Pump; for when 'you have pump’d out fome part of the Air, you fee the Recipient grow dull by the Fall of the Vapours, which the Air, by reafon of its too great Rarefaction, being no longer able to fudain, they fall in fine little Drops upon the Glafs which contains them. . I n Places where there are great Wa- - ter-Palls, you fee Vapours perpetually arife, which are nothing but Particles of Water broken by their Impulfe : And . when a Soap Bubble comes to break, one Part of the Water, of which it confids, falls, and the red, being reduc’d to very fine Particles, ufeends in a Vapour. RULE I. For the Equilibrium of Water by its Weight, Water being in one or feveral VefTels, that communicate with each other, has its upper Parts always upon an equal Level : that is, at equal Didances from the Center of the Earth. The EXPLANATION. Fir 5 Plate 6.:. Let A G H C be a recurve Tube, whofe Diameter is equal in.all its Parts; pour fom© e