Tinned tongue

13:33 Apr 17, 2019 

Just to expand slightly on my previous comment: the word "ox" is normally used to refer to "a castrated bull used as a draft animal". However, it can simply mean "a domesticated bovine animal kept for milk or meat; a cow or bull" (both definitions from Oxford online).

The following comment is from the Oxford Companion to Food, under "beef":

"The word derives from Anglo-Norman bœuf; less desirable parts of the animal are referred to in English with the Saxon prefix 'ox' (OXTAIL, OX-CHEEK, etc.), reflecting the social divide which existed in England after the Norman Conquest."
https://books.google.co.uk/books?id=RL6LAwAAQBAJ&pg=PA74

By the way, Mrs Beeton has recipes for sheep's tongues and pig's tongues too, but I don't think those were usually tinned.

13:14 Apr 17, 2019 

There is a whole footnote about this in Arthur Conan Doyle's book. I can't copy it here, but it says that it's "usually beef" and mentions Isabella Beeton, who prefers ox to horse, though, as she said, the latter was often substituted by dishonest dealers for the former.

Best

13:11 Apr 17, 2019 

I agree that "tongue" refers by default to ox tongue, but it may be worth mentioning that the word "ox" should not be taken literally. It may come from an ox, but usually doesn't; it most often comes from a cow. It was actually often called "beef tongue" or "beef's [sic] tongue" in the period of the book. It just means a bovine tongue. The same is true of oxtail; it's not usually literally the tail of an ox.

11:29 Apr 17, 2019 

It is probably impossible to be 100% certain, but I think it is highly likely that 'ox tongue' is right.