CHAP. XXXIV. Of the causes of the Stone.
THe Stones which are in the bladder have for the most part had their first original in the reins or kidnies, to wit,* 1.1 falling down from thence by the ureters into the bladder. The cause of these is twofold, that is, material and efficient. Gross, tough, and viscid humors, which crudities produce by the distempers of the bowels and im∣moderate exercises, chiefly and immediately after meat, yield matter for the stone; whence it is that children are more subject to this disease than those of other ages:* 1.2 But the efficient cause is either the immoderate heat of the kidnies, by means whereof the sub∣tiler part of the humors is resolved, but the grosser and more earthly subsides, and is hard∣ned as we see bricks hardned by the sun and fire; or the more remiss heat of the bladder, sufficient to bake into a stone the faeces or dregs of the urine gathered in great plenty in the capacity of the bladder. The straightness of the ureters and urinary passage may be accoun∣ted as an assistant cause: For by this means the thinner portion of the urine floweth forth, but that which is more feculent and muddy being stayed behinde, groweth as by scale upon scale, by addition and collection of new matter into a stony mass. And as a wick often∣times dipped by the Chandler into melted tallow, by the copious adhesion of the tallowy substance presently becomes a large Candle; so the more gross and viscid faeces of the urine ••••ay as it were at the bars of the gathered gravel, and by their continual appulse are at length wrought and fashioned into a true stone.