Singer semi diamond 1888

Singer must have been the first to introduce the frame that became very fashionable in 1890-1891: the semi diamond. Singer introduced it in 1887 or 1888 (I am not sure). In 1889 they introduced a model on which the strange saddle tube had developed into a real top tube, so when the semi diamond became fashionable, Singer had already stopped building them.
I found an old advertisement in the Dutch magazine 'Kampioen' (march 1888), showing this bicycle and two other models.

The safety you see in the pictures is a heavy bike, clearly one of the early safeties. It is to see in the Batavus museum in Heerenveen, Netherlands. The bike has a lot of characteristic details. The front suspension was used by more factories, but the double rubber blocks on the front fork foot rests are unique for pre-1890 Singer safeties. This bicycle looks quite original, it's a pity the front mudguard is missing.
Hate to say it, but the oil lamp is from 1910 or later and it should be replaced or removed.