as the timing of inflow and outflow of specie money did not always match although this business was done every year cyclically and continuously , when expense was needed before attaining the current money , it was unavoidable to borrow gold and silver from powerful merchants (especially kuramoto [sake brewer ] or kakeya [merchants dealing in finance ]) , putting up their annual rice tax or local special products which were to be sold later as security , and they paid back when such rice tax or products were actually delivered . こうした取引は循環的かつ継続的に毎年繰り返されるが、正貨獲得時期と正貨支出時期が一致するとは限らず、正貨獲得以前に支出を要する場合には、販売予定の年貢米や特産品を担保として有力商人（特に蔵屋敷に出入りする蔵元や掛屋）から金銀を借りて、実際に入ってきた年貢米や特産品をもって返済することになる。
