Here's a circa 1870 telegraph insulator from England in a Salt Glaze U-1364 (measuring 3" wide x 4" tall) incuse mark: "8 Varley's Patent". Mint condition, but is missing the threadless cup insert.

These were uniquely made with threads but designed to help the cement hold firmly to the inner cup. The inner cup according to the patent drawings in Keith Neal's book are threadless- the pin was always cemented into the inner cup. So, this is a unique style insulator that was made during the transition period of strict threadless to threaded pin-type insulators. First email gets it for only $85 plus shipping. Thanks.