A fresh supply of yellow froth (probably the same type of elemental sulfur found in the "cool acid-brine" crater lake at Kawa Ijen) is brought up by the plume and pushed out toward the crater wall.
Bank lending should also be constrained during periods when asset prices are booming - when the froth is piling up.
当资产价格暴涨时，泡沫到处都是，但越是这样的时期，银行发放贷款就越应当得到约束。
3
Two years ago Franck Riboud, the boss of Danone, a French food group, was able to whip up a froth of economic nationalism to ward off the mere threat of a takeover by America’s PepsiCo.