Devey was the firm of Joseph Devey from Wolverhampton. It existed from 1869 until 1887.
They made middle-class and cheap bicycles which are not very specific in details. A bit like Brazier, also from Wolverhampton.
Those bicycles are always the most difficult to identify.
We are lucky the shop of Yesterdays in the Netherlands has one in the collection, the spring has a stamp which clearly shows the model Special Express.
The several bicycle firms of Wolverhampton worked close together. In this bicycle this becomes very clear, since it's almost a Rudge: front bearings and the way they are attached to the fork, rear wheel hub, step. All clearly supplied by Rudge. Compare it to the Rudge nr 2.
There are also differences. There is no serial number, while Rudges were always numbered. And it has a very peculiar brake spoon, never seen it on other bicycles. The age is estimated around 1883-1884, since it already has the modern ball bearing rear hub, but still the oldfashioned straight handlebars.
Click the picture for more pics on my Flickr site.