Screw-cutting machine, bells and a jetting fountain vase
How to balance a bell so a boy can ring it; changing a screw's thread pitch
The lower half of the sheet is filled by a large bench machine for cutting screws, its rollers and interchangeable wheels lettered and four dies or pans ranged beneath. Above it are two bells with their mountings, an ornate jetting fountain vase and two composite bars. The notes explain how to seat a bell's stock so low that it is nearly balanced and a child can ring it, which part of an oak trunk suits the bell's headstock, and how to alter the machine's wheels and brackets to cut threads of steeper or gentler pitch.
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Bench machine for making screws
Turning the central wheel, which holds the blank to be threaded, cuts a new screw M. To make threads more or less steep one changes the wheels S f for the wheels a b or c d, widens or tightens the brackets h e t, and adjusts the plane K and the fastening g; the plane carries the two dies that cut the channel of the new screw.
Balancing a bell so a child can ring it
The bell's pivots are to be set so low that, when it strikes near its middle, the part below the pivot weighs no more than ten pounds over the part above. So balanced, a small boy will be able to ring it.
Oak timber for the bell's headstock
A note beside a tree trunk marks the length a b as good for the stock (mozzo) of the bell, and a separate word identifies the wood as oak. The selection is about finding sound timber for the bell's mounting.