Which preposition to use with magnum

of Occurrences 9%

" It happened that we had in our cellar some fine claret; a few magnums of Léoville, '74, a present from a millionaire friend.

in Occurrences 1%

This had brought on him the nickname of Dr. Bonum Magnum in the time of faction.

ob Occurrences 1%

Illud certe magnum ob quod gloriari possunt formosi, quod robustis necessarium sit laborare, fortem periculis se objicere, sapientem, &c. 4836.

per Occurrences 1%

The whole poem, with its references to old myths, is merely a rehearsal of schoolroom reminiscences, as might have been guessed from the fine Lucretian rhythms with which it begins: Namque canebat, uti magnum per inane

Which preposition to use with  magnum