أنت هنا
قراءة كتاب A Briefe Introduction to Geography
تنويه: تعرض هنا نبذة من اول ١٠ صفحات فقط من الكتاب الالكتروني، لقراءة الكتاب كاملا اضغط على الزر “اشتر الآن"
diuine power? whether the deepenes of the Sea, doth exceede the height of the mountaines? whether mountaines were before the flood? what is the hight of the highest hilles? whether Iland, came since the flood? what is the cause of the Ebbing and flowing of the Sea? what is the original of springs and riuers? what manner of motion the running of the riuers is? with such like, whereof some belong not so properly to this science of Geography as to others. Wee speake onely a word or two of the last, & so proceed. The question is whether the motion of the riuers bee streight, or Circular. The doubts on both sides will best appeare by a figure first drawne: wherein, Let (HMO) be the Meridian of Alexandria in Ægipt, or of the Mouth of Nilus and answerable to the meridian of the Heauens. Another in the Earth (XBY.) Let (B) bee the mouth of Nilus, and (C) the fountaine and head of it. Now the mouth of Nilus, where it runnes into the mediterranian Sea, is placed by geographers in the 31. degree of the North latitud; & the head of Nilus where it riseth is placed by Polomeus in 11. degree of the South latitud, but by latter & more exact geographers in the 14. degree of the Southern latitud, so that the distance betweene the founts & Ostia i.e. betweene (C) and (B) is 45. degrees of a great Circle, which after the vsuall account makes 2700. one eight part of the earths compasse. The quæstion now is, whether the runninge from (C) to (B) runne continually downward in a streight line; or circularly in a crooked line. If it runne in a streight line, as is most agreeable to the nature of the water it must moue either by the line (CEB) or by the line (DB.) By the line (CEB) it cannot moue: for when it is come to (E,) it will stand still. Because from (E) to (B) it must moue vpward, if it moue at all, which is contrary to the nature of water. If therefore it moue by a streight line it can bee noe other, but (BD,) and so from (D) to (B) it shall continually descend; for of all places betweene (D,) & (B) (B) is the nearest to (A.) But then the fountaine must not bee in (B) but higher in (D) which semees altogether improbable or impossible. For first the line (AD) would bee notably and sent by longer then the line (AB) For the compasse of the earth being about 24000. Miles, and the semidiameter (AB,) or (AC) 3828. miles the line (CD,) would bee 1581. miles, which cannot bee true, if as wee haue proued before, the earth bee round, and that the highest hills make noe sensible inæquality. Againe they that dwell in (D) should see the North Pole starre (N) as well as they that dwell in (B,) which also is false. So then the riuer cannot runne either by (EB) or (DB) Runnes it then circularly by the line (CWB?) This seemes probable, and the rather because heereby a reason of the originall of Riuers might more easily bee giuen. For the fountaines (C) lying euen with the superficies of the Sea, the water may easily passe through the hollowes of the earth, and breake out at (C) without ascendinge. But here also are some difficulties: for first wee find by experience that the fountaines of most riuers, and those greate ons too, lye sensibly higher then the plaine surface of the Sea. Againe, if the riuer moue directly round, what should bee the cause that begins and continues this motion? It is a motion besides the nature of the water, and therefore violent, what should driue it forward from the Sea to (C,) and from (C) to (B,) when the water is at (C) or (W,) it is as neere to the Center (A) as when it is at (B,) and therefore it should seeme with more liklyhood it would stand still; for why should it striue to goe further, seeing where it is, it is as neare to the Center as whither it runnes. Or if some violence doe driue it from (C,) towards (W,) yet (as it is the nature of violent motions) the further it goes the slower it will runne, till in the end it stand still, if there bee noe aduantadge of ground to helpe it forward.

As a bowle throwne downe a hill runnes easily and farre, if it once bee sett a going; but throwne vpon the ice (an euen place) it will without any lett at last stand still. Answere may bee made hereunto, that although there bee noe aduantage of the ground, yet the water will still moue forwarde from (C) to (B) because the water that followes, pusheth forwarde that, that runnes afore. Which answere will stand, when a good cause may bee shewed, which forcibly driueth the water from the Sea vnto (C) and out of the fountaine (C;) considering that (after this supposition) they lie both in the same circular superficies. Wherefore seeing, wee cannot without any inconueniency suppose it to moue by any of these lines either streight as (BC) or (BD,) or circular as (BWC) let vs enquire farther.
The most likely opinion is, that the motion of the water is mixt neither directly streight, or circular, but partly one, partly the other. Or if it be circular, it is in a circle whose center is a little distant from the Center of the whole globe. Let vs place fountaines then neither in (C) nor (D) but in (F) I say the water runnes either partly streight by the (FS) and partly circular, from (S) to (B) which motion will not be inconuenient, for the water descending continually from (F) to (S) will cause it still to runne forward; or else wholy circular in the circle (FXB.) And this is most agreeable to truth. For so it shall both runne round as it must doe if wee will escape the otherwise vnauoidable inconueniences of the first opinion and yet in running still descend, and come neerer to the Center, as is most befitting the nature of water, so that wee need not seeke for any violent cause that moues it. Let vs then see what is the hight of (F) the fountaines of Nilus, aboue (C) that is (B) the mouth or outlet of it into the Sea. The vsuall allowance in watercourses is one foot in descent for 200. foot in running, but if this bee thought to much because water will runne awaie vpon any inequality of ground, for euery 500. foote allow one for descent, & so much we may with reason, in regard of the swiftnes of many riuers, yea the most, which in many places runnes headlong, in all places very swiftly (especially Nilus whose cateracts or downfalls are notable) which cannot bee without some notable decliuity of the ground. Thus then the whole course of Nilus being 2700. miles from (F) to (B) the perpendicular or plumb descent of it (CF) will be 5. miles. And so high shall the fountaine stand aboue the mouth, and the surface of the plaine Land (for riuers commonly arise at foot of hills) which is (BXF) swell vp aboue the surface of the Sea (BWC) or (BY) which hight of the Land aboue the Sea although it bee greater then is the height of the highest moũtaines aboue the plaine Land, yet it is nothing in comparison of the whole Earth. And this being granted (as with most probabilitie of reason it may) it will appeare that God in the beginning of the world imposed noe perpetuall violence vpon nature, in gathering togeather, the waters into one place, and being so gathered in keeping them from runing backe to cover the earth. At the first so soone as those hollow channells were prepared, the water did naturally slide downe