The practice of forcing the parts of boilers together with violence, by means of screw-jacks, and drifts through the holes, should not be permitted; as a great strain may thus be thrown upon the rivets, even when there is no steam in the boiler.

I got on board the ship as before, and prepared a second raft; and having had experience of the first, I neither made this so unwieldy, nor loaded it so hard, but yet I brought away several things very useful to me: as, first, in the carpenter's stores, I found two or three bags of nails and spikes, a great screw-jack, a dozen or two of hatchets; and, above all, that most useful thing called a grind-stone.

The trolly is then run into the vault, and the water-tank containing the piña is lifted by screw-jacks, so as to raise the piña into the retort, in which position the tank is then supported by a cross-beam.