Thisiswhatbankerscallspeculation，whichoftencausesvariationsintheexchangesforashortperiodindependentlyofthebalanceoftrade；butinthelongrunwemustgetbacktothisbalancewhichfixestheconstantanduniformruleofexchange。Andthoughthespeculationsandcreditsofbankersmaysometimesdelaythetransportofthesumswhichonecityorstateowestoanother，intheenditisalwaysnecessarytopaythedebtandsendthebalanceoftradeinspecietotheplacewhereitisdue。
IfEnglandgainsregularlyabalanceoftradewithPortugalandalwayslosesabalancewithHollandtheratesofexchangewithHollandandPortugalwillmakethisevident：itwillbeseenthatatLondontheexchangeonLisbonisbelowparandthatPortugalisindebtedtoEngland。ItwillbeseenalsothattheexchangeonAmsterdamisaboveparandthatEnglandisindebtedtoHolland。Butthequantityofthedebtcannotbeseenfromtheexchanges。ItwillnotbeseenwhetherthebalanceofsilverdrawnfromPortugalwillbegreaterorlessthanwhathastobesenttoHolland。
ThereishoweveronethingwhichwillalwaysshowatLondonwhetherEnglandgainsorlosesthegeneralbalanceofhertrade（bygeneralbalanceisunderstoodthedifferenceoftheindividualbalanceswithalltheforeignstateswhichtradewithEngland），andthatisthepriceofgoldandsilvermetalbutespeciallyofgold（nowthattheproportionbetweengoldandsilverincoinedmoneydiffersfromthemarketrate，aswillbeexplainedinthenextchapter）。IfthepriceofgoldmetalintheLondonmarket，whichisthecentreofEnglishtrade，islowerthanthepriceattheTowerwhereguineasorgoldcoinsareminted，oratthesamepriceasthesecoinsintrinsically，andifgoldmetalistakentotheTowerinexchangefortheirvalueinguineasormintedcoins，itisacertainproofthatEnglandisagainerinthegeneralbalanceofhertrade。ItprovesthatthegoldtakenfromPortugalsufficesnotonlytopaythebalancewhichEnglandsendsintoHolland，Sweden，Muscovy，andtheotherstateswheresheisindebted，butthatthereremainssomeofthegoldtobesenttotheMint，andthequantityorsumofthisgeneralbalanceoftradeisknownfromthatofthespeciecoinedattheTowerofLondon。
ButifthegoldmetalissoldintheLondonmarketabovetheTowerprice，whichisusually？。18。0anounce，themetalwillnolongerbetakentotheMint，andthisisacertainsignthatsomuchgoldisnotdrawnfromabroad（fromPortugalforinstance）
asmustbesentintotheothercountrieswhereEnglandisindebted。ItisaproofthatthegeneralbalanceoftradeisagainstEngland。ThiswouldnotbeknownbutfortheprohibitioninEnglandtosendgoldcoinoutofthecountry。ButthisprohibitionisthereasonwhythetimidLondonbankersprefertobuygoldmetal（whichtheyareallowedtosendabroad）at？。18。0