Detail of the top of a Corinthian capital.
As this detail shows, the top surface of the capitals on the Temple of Vespasian - as well as on most others structures - have a raised platform at their centre (on the right here) which supports the weight of the entablature. This means that no weight is put on the delicately carved edges of the capital (on the left here) which might cause them to break. Interestingly, on this capital an extra panel was added to the central platform on top to raise it a couple of centimeters; this kind of alteration is very common on Roman monuments comprising numerous different elements which would all have varied slightly in their dimensions. Unfortunately damage to the capital visible at the centre of this image means that few toolmarks are visible.