In most cases, however, the paper is at once guided as it issues from the machine, through the tub of size, and is thence carried over the skeleton drums shown, inside each of which are a number of fans rapidly revolving; sometimes there are forty or fifty of these drums in succession, the whole confined in a chamber heated by steam. I have seen a paper machine with the sizing apparatus attached, which from the wire-cloth where the pulp first flows on, to the cutting machine at the extremity, measured no less than one thousand feet. The advantage of drying the paper in this manner over so many of these drums is, that it turns out much harder and stronger, than if dried more rapidly over heated cylinders. Some manufacturers adopt a peculiar process of sizing, which in fact answers very much better, and is alike applicable to papers made by hand or by machine, provided the latter description be first cut into pieces or sheets of the required dimensions. The contrivance consists of two revolving felts, between which the sheets are carried under several rollers through a long trough of size, being afterwards hung up to dry upon lines, previously to rolling or glazing. The paper thus sized becomes much harder and stronger, by reason of the freedom with which the sheets can contract in drying; and this is mainly the reason why paper made by hand continues to be so much tougher than that made by the machine, in consequence of the natural tendency of the pulp to contract in drying, and consequently becoming, where no resistance is offered, more entwined or entangled, which of course adds very considerably to the strength and durability of the paper. In making by the machine, this tendency, you will observe, is completely checked.