Unless marked by the maker, say Thomas Kilby or E. Heuse-Lemoine, you probably can't. English 'Best' were, however, usually 3 Iron in that period.
Letters to Young Shooters: (First series) On the choice and use of a gun
Ralph William Frankland-Payne- Gallwey 1892
http://books.google.com/books?id=Eh9DAAAAIAAJ
There is, however, some little uncertainty about our English Damascus. Really good English Damascus barrels, when they can be obtained, are superior to Belgian; but those of English make vary considerably in their excellence. They are also produced in much smaller quantities, and are often difficult to obtain just as required. The Belgian Damascus are more regular as to figure, and more free from 'specks' and 'greys,' than are the English, besides being softer, and easier to work. For these reasons many of our gun-makers find it simpler to procure their barrels from Belgium, as there is a very small percentage of inferior quality imported from that country, and as many as wanted can also be easily procured at short notice. As it is the fashion of English sportsmen to imagine that nothing good in the way of guns or barrels can reach us from the Continent, Belgian Damascus, in order to fall in with this popular delusion, is often sold as English. Still, if a gun is fitted with best Damascus, whether of English or foreign make,
it is of small consequence to the shooter; but the fact remains, that so-called English Damascus is frequently Belgian, and that the Belgian barrels of this manufacture are, generally speaking, more reliable than those made in England.
Relevant discussion here
http://docs.google.com/a/damascuskno...mx7_22ddqshmdq
and
http://www.picturetrail.com/sfx/album/view/20258609