Mouth in thirty one Degrees of North. It flows from South to North, and is in fome Places very broad; but in others narrow, and hath two great Cataracts. The length of it's Course is about fix hundred and thirty German Miles, or Two thoufand five hundred and twenty Italian; which we may reckon to be Three thousand for it's Curvatures. It overflows every Year.

2. THE Niger (i), a River in Africa, (fometimes called Senegal) arifes from a Lake of the fame Name, in 5 Degr. of North Latitude. Some have formerly thought it to proceed from the Nile by a fubterraneous Paffage, because it annually overflows at the fame Time with the Nile. One of it's Mouths is in 11 Degr. of Latitude, but the furtheft is 15 Degr. diftant from the Equator. It flows from Eaft to Weft, and in one Place hides itfelf under Ground, and again emerges. It's Courfe is about 600 German Miles, but lefs if you neglect it's greatest Curvatures, and more if you include them.

3. THE Ganges, in Afia, has it's remote, and not well known, Fountain a great way up in Tartary; fome place it in 35 Degr. of North Latitude, and others further North.

(i) De l'Ifle in his Maps makes the River Niger to lofe it's name at the Lake de Guarde, and from thence to the Sea which in a ftrait Line is 700 British Miles, is called Senegal; and makes the River Gambia to have no Communication with the Niger; but we have no fufficient Proof that there is any fuch River as the Niger: But Mr Snow, late Governour of James Fort on Gambia River, informs me, that the Senegal hath not fo long Course as it is reprefented

It has it's Mouth in the

SECT. IV. Latitude of 22 Degr. and flows from North to South. It's Course is about 300 German Miles, and every Year it overflows it's Banks.

4. THE Oby, a great and every where broad River in Afia, has it's Fountain in the Lake Kan Kifan, among the Mountains of Tartary, in the Latitude of forty eight Degrees North. It has it's Mouth in fixty nine Degrees of Latitude, and runs a Course of about four hundred German Miles, without it's Curvatures. It divides itself in Siberia, into two Branches, or rather fends forth an Arm which makes a Curvature, and returns to it again, and fo forms an Inland, in which there is a City built by the Muscovites and Siberians, called forgoet.

5. THE Jenifa, a River in Afia, hitherto unknown to our Geographers, but taken Notice of by the Muscovites. It is faid to be much greater than the Oby, from which it is diftant eastward, about ten Week's Journey, towards Tartary. There is a Range of Mountains runs for a great Way along it's eastern Banks; and the weftern Shore is inhabited by the [Ton-Guifins]. It overflows the western Shore feventy German Miles every Year in the Spring, when the Inhabitants are forced to betake themfelves, with their Cattle and Tents, into the Mountains on the eastern Shore. Where it begins and ends is not known, but it is thought to run as long a Course as the Oby.

6. [THE Maia or Lena] is far diftant from the Jenifa eastward. The eastern Branches are faid to proceed from the Borders of China, and the Kingdom of Cathaia; if there be fuch a Place. It's Fountain and Mouth are unknown; and it is not reckoned one of the largest fort of Rivers; only we are willing to mention it here, because it has not been taken notice of by any Geographer, no more than the Jenifa and Irtifch.

I

7. THE

7. THE River of the Amazons, (or Rio de Orellana from Francifco Orelli) in America, is thought to be one of the greatest Rivers upon Earth. It's Fountain is in the Province of Quito in the Kingdom of Peru, near the Equator, and it's Mouth, being 15 Leagues broad, is in 2 Degr. of South Latitude. It is faid to run a Courfe of 1500 Spanish Leagues, by reafon of it's great number of Windings, tho' it extends not above 700 in a ftrait Line. Some confound this with, or will have it to be, a Branch of the Miary. It is in fome Places four or five Leagues broad, but it receives it's Water not fo much from Fountains, as from the Rains that fall upon the Mountains of Peru; and therefore is nothing nigh fo broad in the dry Seasons. This makes Travellers difagree in their Defcriptions of it.

8. THE River of Plate, Argyropotamus, or Rio de la Plata, in Brafil, hath it's Fountain in the Lake Xarayes, and receives a Branch from about Potofi, and it's Mouth in 37 Degr. of South Latitude, which is faid to be twenty Leagues broad; but when it overflows, it has a great many Mouths, which are accounted but as one; for at other times it hath not much Water in it. The Inhabitants call it Paranaguafa, i. e. The River like a Sea, as fome obferve.

9. THE Omarânan is likewife a River of Brafil, flowing thro' a long Tract from the Mountains of Peru. These three great Rivers of Brafil, viz. the Orellana, the Rio de la Plata, and the Omarânan, meet in certain mediterranean Parts of Brafil, fo as to form Lakes, from which they again rife feparate.

10. THE River of St Laurence flows between Canada and New-Holland, in North America, and hath it's Fountain in the Lake [Frontenac or] Iro

A a 3

quois.

quois. It's Courfe is no lefs than 600 German Miles.

PROPOSITION XXVIII.

There are Whirlpools and deep Pits found in fome Rivers.

THUS in the River Soame in Picardy, between Amiens and Abbeville, there is a blind Whirlpool, into which the Water rufhes with fuch Violence, that it's clafhing may be heard feveral Miles off. There are many others of this kind.

PROPOSITION XXIX.

River Water is lighter than Sea-Water.

THE Reafon is, because Sea Water hath much Salt in it. From whence it happens, that fome things fink to the bottom in Rivers that floated upon the Sea; as very often heavy loaded Veffels, which were born up at Sea, fink in the Harbour. However, the Proportion between them is various, and they both differ in Weight in divers Places. We commonly fay, they are as 46 to 45, i. e. 46 measured Ounces of River Water equiponderate 45 of Sea Water.

CHAP.

CHA P. XVII.

Of Mineral Waters, hot Baths, and Spaws.

S B

INCE there are feveral Species of liquid Bodies, or Waters, whofe peculiar Properties feem furprizing, it has given Occafion to Geographers to treat thereof; but all of them hitherto, except a bare Recital of their Names, and a fhort Account of fome of the most extraordinary Fountains, have added nothing to give us an Infight into their Caufe. But we shall here treat of them more fully, and explain their Caufes, and alfo fet them in a clearer Light.

PROPOSITION I.

No Water is pure and elementary; but contains other Particles mixed with it, fuch as are found in terreftrial Bodies; and thefe are not only earthy, but also of various other kinds, as Oil, Spirits, &c. But that is called Mineral Water which contains fo many of thefe Particles different from the Nature of Water itself, that from them it acquires fuch remarkable Properties, as affect our Senfes and makes us take notice of it.