Serving jug with RD number

Thanks to Naomi for the ID on my last post.
This jug stands about 225mm tall. I dont even know what era to put this jug into.
I have books on glass RD numbers but none on pottery.
Any help appreciated.
Tim

Rd for 1934. Seen lots of this stuff over the years, but just can't remember a mark.
Dudsons maybe?
There is an impressed mark above??

Thanks Denbydump for the information. I had a look at those 3 digit impressions
but found them impossible to read. The 1934 date spurred me on to look at deco
water jugs on google images. Bingo! it appears to be Carstens pottery located in
Grafenroda Germany. Described as a coffee jug with an unhinged lid. There are a couple
for sale on the net, in a brown ringed colourway.
The only difference i can see with my made in England one is that the handle finish's
flush with the top.
Thanks again,
Tim

It's a Rountrees Cocoa Jug by Carlton Ware: http://www.carltonwareworld.com/rowntrees_cocoa_jugs.htm
Janet

Thanks janetpjohn for the information, and for that great link.
Anyone got a lid ?
Tim