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Throw on two or three pales of water, at different periods, during the setting, which will have the effect to dissolve any small particles of the shells that may formerly have escaped the water. Observe always to leave a vacancy at the top of the cave, of about eight or ten inches at least, in order to give room for swelling of the lime, and filling up with water.
Supposing now the kelp and lime all put into the cave, and no American ash therewith, but that these ashes have been melted down, or dissolved in boiling water, and are converted into a ley; pour that upon the top of the other materials just put into the cave, and fill up with water until the whole is completely saturated therewith; the completion of which will be evident, when the bubbling in the cave ceases to arise. Let the whole now stand for 12 or
