Kerl’s rule (Grammar, p. [41]) is “Within a sentence, the first word of any important beginning may commence with a capital letter.” This rule is probably as precise as can be framed to meet his first example, “Resolved, That our Senators be requested, etc.” His second example, “One truth is clear: Whatever is, is right,” falls within his rule, and our Rule 1. (See page [81], for capitalizing, etc., preambles, resolutions, provisos, etc.) {p174}
When a sentence is introduced obliquely, a capital is not required, even if the passage introduced have quotation marks, and make perfect sense without the introductory prefix, as in the following example:
It is remarked by Parton, that “a man who retains to the age of seventy-nine the vigor of manhood and the liveliness of a boy, cannot, at any period of his life, have egregiously violated the laws of his being.”
2. The first letter in every line of poetry should be a capital.
When on the larboard quarter they descry
A liquid column towering shoot on high,
The guns were primed; the vessel northward veers,
Till her black battery on the column bears.
Falconer’s Shipwreck.
Thereat the champions both stood still a space,