[78-L] a "Two-Faced" record!

[Ron Roscoe]

Folks:
I came across the following 10" black shellac 78:

Blue label side:
OLYMPIC
Baritone with Orch.
"Drink To Me Only With Thine Eyes" [Ben Jonson]
Percy Hemus
17104-A
Matrix 17104-A
Olympic Disc Record Corporation, New York.
[This side has about ¼" of unmodulated groove at the end of the side; recording engineer late getting back from the men's room? :)]

Light green label side:
Symphony Concert Record
Baritone with Orch.  Price $1.00
"Danny Deever" [Kipling-Damrosch] [Walter Damrosch, the conductor?]
George Landers
21155-B
Matrix 17104-B

Both labels match the songs.  Both are acoustically recorded.
Was this a common occurrence?  Anyone know anything about these labels?

Ron Roscoe