I finally added the last missing link to this family of early Hemingray ponies and thought some of you might be interested to see some of these seldom seen pieces together. They date (roughly) from L to R, earliest to latest:
124.2 1873 -1878
124.3 1878 -1885
124.0 1885 -1893 (without drips)
124.0 1893 - 190? This one shown still bears the 1871 patent on the dome, and has the prismic (1895-1899) date for the added drips.
The No.4 continued through the stamp period (1900 - 1910) as a number 4 and was eventually renumbered the No.13, probably being totally phased out at this time in favor of the popular Hemingray No.9