how did you clamp it?
you tighten the seat clamp bolt.
with the crack drilled it could be tightened just enough to hold the seatpost without much risk of it spreading.
If the cracks too bad you could try jewbelee clips. or welders.
@Rincewind started
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you tighten the seat clamp bolt.
with the crack drilled it could be tightened just enough to hold the seatpost without much risk of it spreading.
If the cracks too bad you could try jewbelee clips. or welders.