In order to obtain the best results, there must be absolute dryness, and care must be exercised, not thinking that because it is _tin_ it will be all right. Skill is required to make good tin fillings, as well as when making good gold fillings. Always use tapes narrower than the orifice of the cavity; they are preferable to rolls or ropes. After a few trials it is thought that every one will have the same opinion. A roll or rope necessarily contains a large number of spaces, wrinkles, or irregularities, which must be obliterated by using force in order to produce a solid filling; thus more force is employed, and more time occupied in condensing a rope, than a flat tape; the individual blow in one case may not be heavier than in the other, but the rope has to be struck more blows. The idea that a rope could be fed into a cavity with a plugger faster and easier than a tape has long ago been disproved. Many of the old-fashioned non-cohesive gold foil operators used flat tapes, as did also Dr. Varney, one of the kings of modern cohesive gold operators. The tape is made by folding any portion of a sheet of foil upon itself until a certain width and thickness is obtained. This tape is very desirable in small or proximal cavities where a roll or rope would catch on the margin and partially conceal the view. In the form of a tape, perhaps more foil can be put in a cavity, and there may be more uniform density than when ropes are used. Tapes can also be made by folding part of a sheet of foil over a thin, narrow strip of metal. Fold the tin into tapes of different lengths, widths, and thicknesses, according to the size of the cavity; then fold the end of the tape once or twice upon itself, place it at the base of any proximal cavity, and begin to condense with a foot plugger of suitable size, and if there is a pit, groove, or undercut which it does not reach, then use an additional plugger of some other form to carry the tin to place; fold the tape back and forth across the cavity, proceeding as for cohesive gold. In small proximal cavities a very narrow tape of No. 10, one thickness, can be used successfully. For cavities in the occlusal surface, use a tape as just described, generally beginning at the bottom or distal side, but the filling can be started at any convenient place, and with more ease than when using cohesive gold. In any case if the tin has a tendency to move when starting a filling, "Ambler's left-hand assistant" is used, by slipping the ring over the second finger of the left hand, letting the point rest on the tin. This instrument is especially valuable in starting cohesive gold (see Fig. 6). This is the easiest, quickest, and best manner of making a good filling, relying upon the welding or cohesive properties of the tin. Many operators have not tried to unite the tin and make a solid mass; they seem to think that it cannot be accomplished, but with proper pluggers and manipulation it can be done successfully.