A distributor bar, opened

The Letter That Finds Its Way Home

A cast line returns as a jumble of brass letter molds. Give one to the bar. Its surviving teeth carry it until the metal beneath them disappears, and then gravity finishes the sort.

First layer

Put the matrix on the rail

Drag the brass matrix onto the distributor, or use the send button. Change any tooth and send it again.

fixed distributor bar, revolving screws carry the matrix

Drag the matrix onto the long metal bar

Ready.

Surviving tooth pairs

The address under your fingers

Second layer

Not merely a sorter

Read a surviving tooth as on and a cut tooth as off. The seven positions then have successive doubling weights. This is a mathematical reading of the mechanism, also printed in later trade literature. It is not a claim that the inventor described his machine in modern coding language.

The company guide counts every nonconstant pattern made by cutting some, but not all, of the teeth. The main and widest auxiliary magazines consume all but one of those patterns. The guide names the full-tooth matrix separately: it is pi, held for the whole bar and sent to the sorts stacker.

This is an address code, not an error-correcting code. A damaged tooth can send a matrix elsewhere. Nothing in the sources promises repair.

The complete census

Touch every possible matrix

Each cell is built in your browser. Choose one to load its teeth into the brass matrix.

Building the census...

The instrument watches itself

The check

The browser takes three routes: enumeration, closed-form arithmetic, and a tooth-against-rail simulation. A published company count is the anchor. Then a deliberately damaged six-position model must miss that anchor.

Choices and uncertainties

  • The drawing is a schematic. Its spacing, speed, and drop timing are explanatory choices, not measurements of a particular machine.
  • The two physical sides carry matching tooth sets. The page collapses each matching pair into one logical position, not two independent positions.
  • The standard main and wide auxiliary counts belong to the configuration named by the company guide. Other Linotype models and magazines used other channel counts.
  • The low cuttable code left after the documented channel allocation is marked unassigned. The primary sources checked here do not explain why it was left unused.
  • The pi route, the empty mask, and the unassigned mask are all explicit refusal or special states. The checker tests each one.

The metal record