10. Books with valuable bindings, if it is necessary that they should be sent through the post, might be well secured in strong boards; valuable papers or prints should be enclosed in strong paper, linen, parchment, or other material which will not readily tear or break. Fragile articles of value (which should by all means be registered, as special care will then be taken of them in all respects) might best be enclosed in wooden boxes, and then wrapped in paper. 11. It is hardly necessary now to point out that the postage-stamp should be placed on the upper right-hand corner of the envelope, and the address written as much towards the left hand as possible; the address will then be removed from the stamp and the postmark of the office, which will be impressed upon the letter before it is despatched. Delay is caused to the Post-Office operations when the stamp is otherwise placed; and in cases which occasionally occur, where the stamp is placed at the _back_ of the letter, it frequently happens that it is sent away charged with the unpaid postage. 12. The penny receipt-stamp will not, under any circumstances, serve the purpose of the penny postage-stamp, though many people would seem to think differently; all letters bearing a receipt-stamp are, of course, charged as if unpaid. The two kinds of stamp might easily be assimilated, and there are rumours that this may soon be done; but they have their distinct duties at present, and the one cannot take the place of the other. 13. The Post-Office stamped envelopes (which may be obtained singly, in part packets, or entire packets, of two or three sizes, and embossed with either penny or twopenny stamps) are in every way the most secure; and if the paper were of better quality, would be quite as economical, as if the ordinary envelope and the ordinary stamp were used. All risk of the stamps becoming detached is, of course, avoided by the use of stamped envelopes. 14. In place of affixing penny postage-stamps according to the weight of a letter, however heavy it may be, application might be made for twopenny, fourpenny, sixpenny, or shilling labels, as the case may be. 15. In affixing stamps, care should be had lest by excess of moisture all the gum be washed off.[188] The practice of dipping the stamp in water is objectionable, except some absorbent be used immediately to remove any unnecessary moisture. It will be found to be a good plan to wet slightly the gummed side of the stamp, and also the right-hand corner of the envelope, and then to keep the finger gently on the stamp until it is firmly fixed. Highly glazed envelopes should be avoided.