2. Glass jars with glass tops fastened by a wire clamp, plus the rubber ring. The tops are usable again and again. 3. Glass jars with flat metal tops held on temporarily by a metal clamp until firmly sealed and then taken off. These look neat and ship-shape, but the top must be punctured before its removal and therefore new caps must be bought each time. 4. Glass jars with flat metal cap over the rubber ring and a bracelet ring with thread and overlapping top edge which, when screwed over, holds the top securely. These tops can be used indefinitely. 5. Glass jar with hermetic seal with lacquered metal top; around the inner edge of the top is a narrow lining of a composition which, when heated, softens and sticks to glass, and while the adhering is going on a wire clamp holds it together and is removed after it is sealed. It is self-sealing but you are unable to remove cover if for any reason during the processing it has to be removed. The government has this to say about the types mentioned above: “If the old-fashioned screw-top jar is used (No. 1), good caps are essential for safety. After having been used the edge of this cap becomes flared and the porcelain lining frequently is loosened from the top. This lid then not only is difficult to sterilize but may fail to give an air-tight seal. If such jars are on hand and must be used, it will be better to use them for the canning of fruits, preserves, and other products which are easily processed and to secure jars of the lightning-seal type for vegetables which are more difficult to preserve.” In preserving it is always well to put a three-ply hot towel underneath the jar when pouring hot material into the jar to insure against breakage--_especially_ when the table has a glass or porcelain-like top. SEALING TESTS If, after twenty-four hours, the seal or hermetic jars can be lifted by their lids without falling from grace or from anything else, the seal is pretty sure to keep the contents in good shape. Screw-top jars can be tested by inverting in order to discover leakage. All jars should be tested and reprocessed if jars leak. Sad to say, foods in the best seal containers are often ravaged by the culinary Bolsheviki which are bacteria forming in the most airless jars. Unless all the bacteria are killed in processing, the tight seal is no indication of salvation.