No record of this gentleman has been found in any of the directories, and though no dates are known everything about this sole cdv speaks of the early 1860s. A photographer named Henri Everard is recorded at this address for one year in 1860, so there probably was indeed a studio there.
The card is shorter than the standard size, but there is some evidence that it may have been trimmed. It seems to be characteristic of some of the early cdvs that the head of the central figure is placed at the intersection of the diagonals, a low position compared to later practice. To our eyes, it leaves a lot of 'wasted space' above. (cf examples from LOW and WHITE)