Line of Identity
The line of identity is a Graph any replica of which, also called a line of identity, is a heavy line with two ends and without other topical singularity (such as a point of branching or a node), not in contact with any other sign except at its extremities. Otherwise, its shape and length are matters of indifference. All lines of identity are replicas of the same graph.
A heavily marked line without any sort of interruption (though its extremity may coincide with a point otherwise marked) shall, under the name of a line of identity, be a graph, subject to all the conventions relating to graphs, and asserting precisely the identity of the individuals denoted by its extremities.
A heavily marked continuous line on the sheet of assertion shall assert that the individuals denoted by its two extremities are identical. [—]
Such a line is called a line of identity.
A heavily marked uninterrupted line on the sheet of assertion, having two extremities and no branching shall be called a line of identity and shall be a graph asserting the identity of all the individuals denoted by its points (all which being heavily marked denote individuals).