The correct spelling of the second name is "Pryse". While the Webley revolvers were in production, there were many "improvements" made by others in their operation and construction. The Pryse latch sysem was one of those, and one that Webley adopted and produced for a while. Webley-Pryse revolvers were fairly popular and are relatively common today in the US. (Most handguns in the UK have been seized and destroyed by the government, of course.)
Much more info is available both on the "net" and in books.
Jim