northern Declination, and the shortest Day and longest Night when he hath the greatest Southern.

Theor. 27. In all Places between the Equator and South Pole, the longest Day and the shortest Night is always when the Sun hath the greatest fouthern Declination; and the shortest Day and longest Night, when the greatest Northern.

Theor. 28. In all places fituated under the Equinoctial Line, the Meridian Shadow of a Style perpendicularly erected, doth caft itself towards the North for one half of the Year, and towards the South during the other.

Theor. 29. In all places lying under the Equinoctial Line, there is no Meridian-Shadow on those Days of the Year that the Sun doth enter the Signs of Aries and Libra.

Theor. 30. The nearer that Places are unto, or the farthest removed from, the Equator, the fhorter or longer accordingly is the Meridian-Shadow of a Style perpendicularly erected in fuch Places.

Theor. 31. The farther that Places are removed from the Equator, yet not furpaffing 66 Degrees of Latitude, the greatest is the Sun's Amplitude, or that Arc of the Horizon between the Points of due East and Weft, and those on which the Sun rifeth and fetteth on the Days of the Summer and Winter Solstice.

Theor. 32. In all places lying under the fame Semicircle of the Meridian, the Hours of both Day and Night are always the fame in one as in the other.

Theor. 33. In all places both of the North and Southern Hemifpheres, that lie under the oppofite Parallels of Latitude, the Seasons of the Year are not the fame in one, as in the other.

Theor. 34. In all places fituated in a parallel Sphere, the Circle of the Sun's Diurnal Motion

runs

SECT. VI. runs always parallel, or very near it, to the respec tive Horizon of fuch places.

Theor. 35. In all places fituated in a right Sphere, the Circle of the Sun's Diurnal Motion is ftill perpendicular, or very near it, to the respective Horizon of fuch places.

Theor. 36. In all places fituated in an Oblique Sphere, the Circle of the Sun's Diurnal Motion is always oblique unto, or cutteth, the Horizon of fuch places at unequal Angles.

Theor. 37. If the Difference of Longitude in two Places be exactly 15 Degrees, the People refiding in the Eastmost of them, will reckon the time of Day fooner by one Hour, than those in the other. If the Difference be 30 Degrees, then they'll reckon the Hours fooner by two; if 45 Degrees, by three; and if 60, then by four, &c.

Theor. 38. If People refiding in two diftinct places do differ exactly one Hour in reckoning their Time, it being only Noon to one, when One in the Afternoon to the other, the true Distance between the respective Meridians of thofe Places is exactly 15 Degrees upon the Equator: If they differ two Hours, the Distance is 30 Degrees; if three, 'tis 45; and if four, 'tis compleatly 60, &c.

Theor. 39. If any Ship fet out from any Port, and fteering Eastward doth entirely furround the Globe of the Earth, the People of the faid Ship in reckoning their time will gain one Day compleatly at their Return, or count one more than thofe refiding at the faid Port: If Weftward, they'll lofe one, or reckon one lefs.

Theor. 40. If two Ships fet out from the fame Port at the fame time, and both furround the Globe of the Earth, one steering East and the other Weftward, they'll differ from one another in reckoning

their

their time two Days compleatly at their Return, even suppose they happen to arrive on the fame Day. If they furround the Earth twice, fteering as aforefaid, they'll differ four Days; if thrice, then fix, &c.

Theor. 41. If feveral Ships fet out from the fame Port, either at the fame or different time, do all furround the Globe of the Earth, fome fteering due South, others due North, and arrive again at the fame Port, the respective People of thofe different Ships at their Return will not differ from one another in reckoning their time, nor from those who refide at the faid Port.

GEOGRAPHICAL PARADOXES, With their SOLUTIONS.

Paradox 1. There are two remarkable places on the Globe of the Earth, in which there is only one Day and one Night throughout the whole Year.

Solution. Thofe two places are mostly all that Space contained within the Polar Circles, as is evident from Prob. 15.

Paradox 2. There are alfo fome places on the Globe of the Earth, in which there is only one Day and one Night at a certain time of the Year.

Solution. Thefe two places are the Polar Circles, when the Sun is in the oppofite Tropic, as appears from Prob. 15 and 16.

Paradox 3. There is a certain place of the Earth, at which if two Men fhould chance to meet, one would stand upright upon the Soles of the other's Feet, and neither of them fhould feel the other's Weight, and yet both fhould retain their natural

Pofture.

VOL. II.

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Solution.

Solution. This place is the Center of the Earth: This Paradox is rendered obfcure, by faying a certain place of the Earth, and not in the Earth.

Paradox 4. There is also a certain place of the Earth, where, a Fire being made, neither Flame nor Smoak would ascend, but move circularly about the Fire. Moreover, if in that place one fhould fix a smooth or plain Table without any Ledges whatsoever, and pour thereon a large Quantity of Water, not one Drop thereof could run over the faid Table, but would raise itself up in a large Heap.

Solution. This is likewife the Center of the Earth; but these two last Paradoxes may rather be termed Philofophical than Geographical.

Paradox 5. There is a certain place of the Globe, of a confiderable Southern Latitude, that hath both the greatest and least Degree of Longitude.

Solution. Not only a certain place in Southern Latitude, but all places, fituated under the first Meridian from Pole to Pole, have the greatest and least Degree of Longitude; because where the utmoft Extent of Longitude ends, it's leaft Denomination begins.

Paradox 6. There are three remarkable places on the Globe, that differ both in Longitude and Latitude, and yet all lie under one and the fame Meridian.

Solution. This is to be understood of the Artificial Globe, and the brazen Meridian thereto belonging; then the Difficulty will foon vanish, if we fuppofe the first place to be fituated 10 Degrees of Latitude, and 10 Degrees of Longitude, from any first Meridian, the fecond place under the North Pole, and the third in 190 Degrees of Longitude under the Tropic of Cancer: Then it will appear, that all three places are under the fame brazen Meridian of the Artificial Globe, and yet differ both in

2

Longitude

Longitude and Latitude, for the first place will be in 10 Degrees Longitude and 10 of Latitude; the fecond in o Longitude and 90 Degrees Latitude; the third in 90 Degrees Longitude and 23° 30' Latitude.

Paradox 7. There are three remarkable places on the Continent of Europe, that lie under three different Meridians, and yet all agree in Longitude and Latitude.

Solution. 'Tis fupposed that this refers to the Difference among Geographers in fixing their firft Meridian. Thus fome place it at Cape de Verd Inlands, and others at Teneriffe, one of the Canary Islands. Now if you take three places in Europe to make it correfpond with the Paradox, in the fame Latitude, at 10 Degrees diftant from one another, and fuppofing each place to be the first Meridian, they all agree in Latitude, and alfo in Longitude, and yet lie under three different Meridians in refpect of the Globe.

Paradox 8. There is a certain Inland in the Egean Sea, upon which if two Children were brought forth at the fame inftant of Time, and living together for feveral Years, fhould both exfpire on the fame Day and Hour, yet the Life of the one should furpafs the Life of the other by divers Months.

Solution. This Paradox may be folved two ways:

1. If one of the Children fail directly East, and the other directly Weft, when they encompass the Globe, which may be done in a Year, there will be two Days difference in their Ages; and in 40 Years thus failing, the one will be 80 Days older than the other.

2. Otherwife, if we fuppofe the one to live within the Artic Circle, where no Day exceeds 24 Hours; and the other lives within either of