If it's weight stamped in CWT then it's an English anvil; does it weigh close to 165#?  The configuration---fat waisted is also typical in older English anvils.  Unfortunately there were over 200 different English anvil Makers over the years and as a lot of them learned the trade working in either Mousehole or Peter Wright it can be difficult to pin down the exact maker---you can have 2 identical anvils side by side and they could still have different makers!

The side prong means it was originally sold as a coachmaker's anvil---the projection was for forging clips to use for fastening wood and metal together, (or wood and wood).

Does the pritchel hole show any signs of being drilled rather than hot punched?   If it was a retrofit feature than the anvil would be most likely pre 1830, if it was original, post 1830. (That feature became more and more common during the 1820's.)

William Foster was the only English anvil maker I know of that date stamped their anvils; others can be dated by guessing at their configuration and, if legible, the style of their trademark stampings for manufacturers whose stampings evolved over time.

If it passes the bounce and ring tests it's a good anvil no matter who made it and vice versa!

For a good solid guess on the date: "19th century" is most likely!  Of course anvils are not considered old until they get 200+ years on them; you can look at "colonial anvils"  and see how they differ.  (We get a lot of people excited that their anvil is over 100 years old; till they find that many of us are using blacksmithing equipment that's 100+ years old; I've got a postvise that I still use that's 200+ years old, pre 1800 according to an expert, Frank Turley)

Fascinating!  The anvil weighs 162.4 pounds so I surmise that it is indeed English made.  The pritchel hole is smooth and doesn't show any signs of being drilled.  So it appears to be post 1830.  The best thing about it... it does pass the ring and bounce test and has a lot of life in it as well as being a family heirloom.  I am very glad I found this site!  Thanks for the info ThomasPowers!!!

Yup 162# on a calibrated scale is close enough to 165# on a "historic" one.  Sounds like a keeper---now get a move on and use it!