CSX milepost prefixes in Waycross, Georgia, 587 miles south of Richmond on the branch to Montgomery, Alabama (which splits near milepost 548 in Jesup). Three-letter prefixes are used for minor branches of these branches, or minor branches off the mainline - for instance ANA is the northernmost branch of AN. Before the ACL merged into the Seaboard Coast Line Railroad in 1967, none of the prefixes had the initial "A". The letters "I" and "Q" were skipped, and double-lettered prefixes (like KK, which would be AKK post-1967) were not used. A is given to the main line from Richmond, Virginia to Port of
Three letter rule and "ka". Carney calls such words "exceptions which prove the rule, clearly marked as exotic by the spelling". Three letter rule In English spelling, the three letter rule (or short word rule) is the observation that one- and two-letter words tend to be function words such as "I", "at", "he", "if", "of", "or", etc. As a consequence of the rule, "content words" tend to have at least three letters. In particular, content words containing fewer than three phonemes may be augmented with letters which are phonetically redundant, such as "ebb, "add, "egg, "inn, "bee, "awe, "buy", "owe", etc. Many content