grep ... cannot escape the "." metacharacter.

[Dave Lee]

I'm sure there must be an explanation for this but
I can't find it in the literature and it seems to 
contradict the man page for grep. I'm using 2.4.2.
Consider:
$cat > testf
>19:53
>19x53
>19.53
>19 53
$grep 19\.53 testf
19:53
19x53
19.53
19 53
...and I get the same result with -E and -e.
Surely this is not a bug... .but How Do I Escape A "." ???
Sincerely, and esasperatedly,
-Dave Lee

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