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- .s, they don't lofe it, but only ceafc to enjoy the Pri-
vileges of their Noblefle while their Commerce conti- nues, and reaffume ir, by giving over Trade, without any Letters or Iniirument or" Re-Habilitation. In Republicsit is {till more valued : bur no where more than in England, where the younger Sons and Brothers of Peers are fre- quently bred up to Merchandize. Add to this, that many ui ihe Italian Princes are the principal Merchants of their States J and think it no difcrcdit to make their Palaces ierve as VVarehoufes : And that many of the Kings of stjia, muft of thofe of the Coait of sifnea and Guinea, trumck with the Europeans, fometimes by their Mini- ikrs, and fometimes in Perfon
The Qualifications rcquifite for the Profeffion of a Merchant, are, i. To keep Books, tingle or double, -viz. Journals, Ledgers, and others: 2. To draw Invoices, Contracts Charcer -Parties, Policies of AfTurance, Bills of Exchange, Letters Miffivc, £f?tr. 3. To know the Rela- tion between the Monies, Weights, and Meafures of fe- veral Countries. 4. The Places where the feveral Kinds of Merchandizes are manufactured, in what manner made, what the Materials compofed of, and whence 5 the Pre- paration the Materials require before they are wrought j and the Merchandizes atierwards. 4. The Lengths'" and Breadths of Stuffs, as Silks, Wools, Hairs, Linens, &c u the Regulations of the Place where they are manufactured, and their different Prices at different Seafons. 5. The Dying, and the Ingredients for the Formation of the different Colours. 6. The Merchandizes that abound, or are 1 more rare in one Country than another; their Kinds and Qualities i and the manner of Trafficking them to the belt Advantage, whether by Land, by Sea, or Rivers. 7. The Commodities permitted or prohibited, both for thelmportand Export of a State. 8. The Price of Ex- change according to the Courfe of feveral Places, and what it is that railes or lowers it. y. The Duties to be paid both at the Import and Export of Wares, according to* the Ufeof the Places, theTarifs, Regulations, ££c. 10. The manner of Packing, Baling, and Tunning Merchandizes, to .keep them either in Magazines, or in Voyages, &c. 11. On what Terms a Merest- Veffel may be Freighted, and Affured. 12. The Goodnefs and Value of every thing requisite for the Cooilruction or Refitting of VeiTels, the Prices of Woods, Cordage, Malts, Anchors, Sails, and other Equipage. 15. The Wages ordinarily given Cap- tains, Officers, and Sailors : and the manner of contrac- ting with them. 14. Theforeign Languages, which may be reduced to three principal ones, -viz. the Sfaritjh, ufed almofi through all the Eaji, particularly on the Coaft of Africa, from the Canaries to the Cape of Good Hope 5 the Italian, ufed throughout the Coalts of the Mediterranean, and many Places of the Levant 5 and the Teutonic or Ger- man, ufed throughout mofl Countries of the North. Laftly, theConfular Jurifprudcnce, the Laws, Cuftoms, Compa- nies, Colonies, Chambers of Aflurances, Confuhtes in the feveral Countries ; and in the general, all the Ordon- nances, Regulations, and Policies, relating toCommerce.
MERCHANT, a Perfon who carries on Merchandize, or fultains the Mercantile Profeffion. See Merchan- dize.
Merchant-Maw. SeeSmp, Vessel, Captain, &c-
MERCHANT-%/on Company'^ cCompany.
Merchant-Taj /or j School 5 C £ School.
Merciianlace, fee Law.
MERCATOR's Charcot FryeSiionjs a Sea Chart, where- in the Parallels are reprefentcd by itrait Lines ; and the Meridians, likewife, by parallel flrait Lines, whofe De- grees, however, are not equal, but are continually en- larged as they approach nearer the Pole, in the fame Pro- portion as the parallel Circles decreafe towards them. See Projection.
For the Conftruction, Lfe, Advantages, £S?c. hereof, fee Mercator's Cj.art.
Mercator's Sailing, is that performed by means of Mercator's Charts. See Mercator's Sailing.
MERCURY, 9, in Aftronomy, the fmalleft of the in- ferior Planets, and the neareif the Sun. See Planet and System.
The mean Diflance of this Planet from the Sun is to that of our Earth from the Sun as 387 to 1000 j its Excentricity 8 Degrees: The Inclination of its Orbit, that is, the Angle formed by the Plane of its Orbit with the Plane of the Ecliptic, is 6 Degrees 52 Minutes: Its Diameter to that of the Earth as 3 to 4 5 and therefore the Globe of Mercury will be to that of the Earth as 2 to 5. See Excen- tricity, Inclination, Diameter, Distance, ££c.
According toSir I!. Newton, the Heat and Light of the Sun on the Surface of Mercury is feven times as intenfe as on the Surface of our Earth in the middle of Summer : which, as he found by Experiments made for that pur- pofe by a Thermometer, is fufficient to make Water boil. Such a degree of Heat therefore muft render Mercury un-
cm)
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inhabitable to Creatures of our Conftitution : Arid if Bodies on its Surface be not inflamed and fet on fire it mull be becaufe their Degree of Denfitv is proportionably greater than ttiat of fech Bodies with us, See Heat.
The Revolution of Mercury round the Sun, or his Year is performed in 87 Days, 23 Hours; his diurnal Revolu- tion, or the Length of his Day, is not yet determined ; nor is it certain whether he has fuch a Motion round hii own Axis, or not. See Period, Revolution, £gc".
What variety of Weather or Seafons it may 'be liable to we are (1,11 at a lofs; as not knowing the Inclination of his Axis to the Plane of his Orbit. The Force of Gra- vity on the Surface of Mercury, is feven times as ftrong as on the Surface of the Earth. Its Denfity, and, conse- quently, the Gravitation of Bodies towards the' Centre cannot be accurately determined ; but no doubt it mult exceed that of our Earth, by reafon of the Excefs of Heat there. See Gravity, Density, ci?c.
Mercury changes its Phafes, like the Moon, according to its feveral Poiitions with regard to the San and Earth; See Moon.
It appears full, in its fuperior Conjunctions with the Sun, becaufe we can fee the whole illumined Heini- fphere : But in its lower Conjunction, we only fee the obfeure, or unillumined Hemifphere : In his Approach toward the Sun, his Light is falcated or horned. See Phases.
The Situation of this Planet proves evidently, that the Hypothec's of Ptolemy is falfe : For Mercury ' is fome- times obfervtd betwixt the Earth and Sun ; and fome- times beyond the Sun. But the Earth is never found be- tween Mercury and the Sun 5 which however muft happen if the Spheres of all the Planets incompafs'd the Earth' as a Centre, according to the Ptolemaic Scheme. See Ptolemaic Sy/lem.
The Diameter of the Sun view'd from Mercury, would appear three times as big as it appears on our Earth ; that Planet beins; thrice as near him as we are ; and there- fore the Sun's Disk would appear feven times as large as it appears to us.
Its greater! Diilance from the Sun, with regard to us, never exceeds 28 Degrees, whence 'tis feldom vifible 5 being commonly cither loll in the Sun's Lighr, or, when the moil remote from the Sun, in the Crepufculum.' The belt Obfervationsof this Planet, are thofe made when it is feen on the Sun's Disk 5 for in its lower Conjunftion, it paltes before the Sun like a little Spot, eclipfing a fmall part of his Body, only obfervable with a Telefcope. The firll Obfervation of this kind, was that of Gaffeitdi in J1J32. See Transit.
To an Inhabitant of Mercury, the folar Spots will ap- pear to ttaverfe his Disk fometimes in a right Line from Eaft to Weft, and fometimes Elliptically. As the other five Planets ate above Mercury, their Phatnomena will be nearly the fame there, as with us. Vemu and the Earth when in opposition to the Sun, will jhine with full Orbs' and afford anoble Light to thatPIanet.
Mercury, in Natural Hittory, afluid, mineral Matter perfeaiyrefembling Silver in fufion. See Mineral. '
Mercury is known under a great number of Names s The common Name among theAntients was Hydrargyrum q. d. Water of Silver. The Moderns commonly call ir Mercury, from fome fuppofed Relation it bears to the Pla- net of that Name. In Englifi it is popularly call'd Quick- silver, from its Appearance. Many of the Chymifts call it Proteus, from the variety of Forms, Colours, igc. it paffes thro' in their Preparations.
Naturalifts are divided what Clafs of Foflils to range Mercury under : Some make it a Metal i others a Semi* metal; and others an imperfeft Metal. See Fossil and Semi-metal.
Boerhaave obferves, that it is very improperly call'd a Metal, inafmuch as it has not all the' Characters of fuch a Body ; nor fcarce any thing in common with the other Metals, except Weight and Similarity of Parts : Thus for Example, it is neither diffolvable by Fire, malleable,' nor fix'd : In effect, it Teems to constitute a peculiar Clafs of Foflils : and is rather the Mother, or Balis of all Metals, than a Metal itfelf. See Metal.
Perfect Metals, according to M. ttomberg, Jjjc. are no- thing hut pure Mercury, whofe little Particles are penetra- ted on all fides, and HI I'd with the Matter of Light, which unites and binds them together into a Mafs, fo that the Parts of fluid Mercury, which are fuppofed to be little folid Globes, in their Metallifieation are render'd rough and un- even, being pireced on all fides, and having their Pores or Perforations fill'd with the Matterof Light. By fuch means they lofe their firft Confirmation, and the Politure or Smoothnefs of their Surfaces, which is one of the principal Caufes of the fluidity of Mercury.
The Chymifts make Mercury one of their Hypofiatical
Principles : Nor, as M. Homberg obferves, that it anfwers
U u u u u u the
