Which preposition to use with diagonal

of Occurrences 4%

the side and diagonal of a square, whereof the diagonal is an inch long, he may have the idea also of the division of that line into a certain number of equal parts; v.g. into five, ten, a hundred, a thousand, or any other number, and may have the idea of that inch line being divisible, or not divisible, into such equal parts, as a certain number of them will be equal to the sideline.

from Occurrences 2%

The Persimmon was a queer-looking negro; his head was a long diagonal from its peak down to his pendent lower lip, for he had no chin.

to Occurrences 2%

The instant they had fairly moved away, she turned and ran in, in a hurry to look after the salt-cellars, and to see that Katty hadn't got the table-cloth diagonal to the square of the room instead of parallel, or committed any of the other general-housework horrors which she detailed herself on daily duty to prevent.

at Occurrences 1%

The four corner guy ropes are then placed over the lower notches of the large pins driven in prolongation of the diagonals at such distance as to hold the walls and end of the tent vertical and smooth when the guy ropes are drawn taut.

Which preposition to use with  diagonal