Premier Double Hollow Fork models

Hillman, Herbert & Cooper built all kinds of ordinaries. This DHF (Double Hollow Forks) was top of the line for eight years.
It was introduced in 1878 by HHC and Singer: the patent was written on both names. Singer built a few, but HHC continued building these roadsters, which were considered light around 1880. It also was one of the first designs that used front wheel brake. The DHF-model is beautiful to see, with its open steering head.
It's not specifically rare, since a lot of these high classed bikes have been saved in sheds and museums. The DHF was built until 1886.

In the first years they were still offered with plain bearings, but most customers chose the optional double ball bearings, which all remaining bicycles have. 

Earliest models (1879-1881?) still have open tubes on top of the head. Tubes filled with water and broke when it froze.  Later models have closed tubes. 
Look at my HHC serial nr. chart

'79 DHF (rear wheel brake)
 DHF with open tubes
 DHF with closed tubes