3. Tin cans can be piled one above the other.
4. When the canner has been filled fasten the opposite clamps moderately tight. When this has been done tighten each clamp fully.
5. Have the canner absolutely steam-tight.
6. Allow the pet cock to remain open until live steam blows from it.
7. Close the pet cock.
8. After the gauge registers the correct amount of pressure, begin counting the time.
9. Maintain a uniform pressure throughout the process.
10. When the process is completed allow the steam to escape gradually through the pet cock. You can lift the pet cock slowly, using a pencil or a knife. This can be done only with tin cans. If glass jars are used the canner must be cooled before opening the pet cock. Blowing the steam from the pet cock is likely to cause a loss of liquid from the partly sealed glass jars.
11. Throw the tin cans into cold water.
12. If tin cans bulge at both ends after they have been completely cooled, it indicates that they are spoiling and developing gas, due to bacteria spores or chemical action. These may be saved if opened at once and resealed or resoldered and processed again for ten minutes.