processing garden produce
fowlers Vacola bottling method
fowlers Vacola stovetop units
Although Fowlers stovetop units are no longer made there are still plenty of second hand ones around (in Australia). They are a very cheap and more environmentally friendly alternative to electric Fowlers units.  See Comparison of Fowlers Units for more details on their advantages and disadvantages.
Photo of two different size Stovetop Fowlers units
Two different sizes of stovetop Fowlers units.  The orange unit on right has a thermometer in the thermometer holder on the side.