The hoops for these sort of globes, may be made of wood, tin, or iron wire, about two feet diameter; for a single globe take two hoops, and fasten them together, one within the other at right angles; then have a horizontal wheel made, whose diameter must be a little wider than the globe, and its nave six inches long, on the top of which the globe is fixed, so as to stand three or four inches from the wheel; on this wheel you may put any number of cases, fill’d with what charge you like, but let two of them burn at a time; they may be placed horizontally or to incline downwards just as you chuse. Now when the wheel is cloathed, fix on the hoops as many illuminations as will stand within two inches and a half of one another; these you fasten on the hoops, with small iron binding wire, and when they are all on, put on your pipes of communication, which must be so managed, as to light them all with the second or third case on the wheel; the spindle on which the globe is to run must go through the block of the wheel, up to the inside of the top of the globe, where must be fix’d a bit of brass or iron, with a hole in it to receive the point of the spindle, on which the whole weight of the wheel is to bear, as is shewn by fig. 46. which represents a globe on its spindle. By this method may be made a crown, which is done by having the hoops bent in the form of a crown. Sometimes globes and crowns, are ordered so as to stand still, and the wheel only to turn round; but when you would have the globe or crown to stand still, and the wheel to run by itself, the block of the wheel must not be so long, nor the spindle any longer than to just raise the globe a little above the wheel; and the wheel cases, and the illumination must begin together. Of the Dodecaedron.