Once, years ago when I lived in its territory, The Dayton Journal Herald ran a vacation-time headline that said approximately, "Everybody Is Out of Town on Holiday."

That didn't explain why something like 100,000 copies of the Journal were being dropped on the doorsteps of those of us who were left behind, not being considered part of those who counted.

Which is by way of admitting that news in this week before Labor Day is running slack, given that President Reagan (who definitely counts) is in California, and the 540 members of Congress are likewise dispersed.

The 540 members of Congress? Hey, wait a minute. The national press, and even The Washington Post, which by local presence claims a cachet of authenticity, invariably refers to 535 members: the 100 senators and 435 representatives, a total of 535. But that falls five short of the true total: four nonvoting delegates (Fofo I.F. Sunia from Samoa, Walter E. Fauntroy from the District of Columbia, Antonio Borja Won Patt from Guam and Ron de Lugo from the Virgin Islands) and a resident commissioner (Baltasar Corrada from Puerto Rico).

Which brings me to correct a colleague's identification last week of Fauntroy as "the first" congressional delegate elected from the District of Columbia. Not so. Norton P. Chipman (R) served from 1871 to 1875, after which the post was abolished until it was revived and Fauntroy won it in 1970.