The Jones Factory, based in England, made a number of treadle sewing machines that are now collectable vintage items. Not only is the craftmenship on them beautiful, but they can be very functional if you know how to use them. If you have a model with a long, barbell-shaped bobbin and a bobbin case or "shuttle" shaped like a bullet, you have what is called a "vibrating shuttle bobbin." It may look complicated compared to modern bobbins, but with a little practice you can use one smoothly.
Hold the bobbin shuttle in your left hand between your thumb and forefinger with the long thread slot facing you.
Drop the bobbin wrapped with thread into the shuttle. When you drop it, the thread should be emerging from under the left side of the bobbin in the centre of the barbell so that you can draw the thread to the right with your right hand.
Pull the thread downward in the long slot with your right hand as far as it will go while pressing down on the top of the bobbin with the forefinger on your left hand.
Pull the thread straight up under the tension spring on the shuttle until the bobbin can smoothly unwind.
Load the shuttle into the shuttle carrier that sits beneath the needle. The point should be facing you and the tension adjusting screw should be facing up. Leave about 3 inches of thread coming from the shuttle.
Close the slide above the shuttle, leaving enough space for the thread to pull smoothly.