If using glass-top jars, with the patent wire snap, put the cover in
place, the wire over the top and the clamp up.

The cover on a glass jar must not be tight while processing, because
the air will expand when heated, and if the cover is not loose enough
to allow the steam to escape, the pressure may blow the rubber out or
break the jar.

When canning in tin we cap and tip the cans at once. The tin will
bulge out, but is strong enough to withstand the pressure, and when
the contents cool the can will come back into shape.

The jars are now ready for the canner. Tomatoes sterilized under
boiling water require twenty-two minutes; in condensed-steam cooker,
twenty-two minutes; in water-seal, eighteen minutes; in
steam-pressure, with five pounds, fifteen minutes, and in the pressure
cooker, at ten or fifteen pounds, ten minutes.

If you use the homemade outfit or any water-bath outfit be sure the
water is boiling when the jars of tomatoes are lowered into the
canner. Time lost in bringing the contents to the point of
sterilization softens the tomatoes and results in inferior goods. Use
the ordinary good sense with which you have been endowed in handling
the jars and you will have no breakage. At the end of the sterilizing
period, remove the jars.

In taking canned goods from boiling hot water, care is needed to see
that they are protected from drafts. If necessary close the windows
and doors while lifting the jars out, for a sudden draft might break
them.