If Archibald Knox and Liberty had made a chimneypot, this would have been it: an Arts & Crafts down draught preventer with built-in rain guard. It is clearly stamped 'FAWCETTS PATENT No2214 1906'. Two businesses named Fawcett seem likely candidates Mark Fawcett & Co, constructional engineers, and T Fawcett, makers of clayworking and brickmaking machinery. One of the Fawcetts invented a fireproof floor system and supplied chimneypots to Marlborough House in London - but we cannot trace photos showing the Fawcett's Patent pots on the roof (see postscript below).
 
There seem to be plenty of places where this model of chimneypot is extant on roofs in coastal towns of southern England on Flickr.
 
John Gall, formerly of Beamish Museum, has sent in a photo of a Fawcett's patent chimney pot. What, he wondered, was the purpose of the dished rain cowl, why concave and not convex like all other chimneypots? There is no obvious answer. Could the downdraught qualities be improved by that shape? Did anyone have a scientific system to measure that anyway? Was the designer a bird-lover providing a convenient nest site? Why was the bowl glazed?
 
A contemporary newspaper cutting from the London Evening Standard states:

Messrs Mark Fawcett & Co, 50 Queen Anne's Gate, make a display of their Edwardian patent down draught preventing chimney pots, a number of which they have lately fitted to Marlborough House. It is a scientific and inexpensive chimney, which effectively prevents the smoke from a fire blowing into the room, while at the same time it retards the escape of heat. It is artistic in design and strongly made, and those who suffer from smoky chimneys would do well to examine the invention.

The 'Edwardian Down Draught Preventing Chimney Pot' was marketed in newspapers around Britain between 1907 and 1913, and seems a likely candidate to be the Fawcett's patent, but we cannot be certain because we have not found an illustration.
 
There were two universal exhibitions in 1906 - Milan and New Zealand - but again there is no trace of the Fawcett pot.
 
Poscript: Just discovered an obituary for Mark Fawcett who died in November 1915 aged 55 while sculling on the Thames. The obituary in Building 109 reads: 'Mr. Fawcctt was also the patentee of the "Edwardian" chimney-pot.' He had trained in Lincoln, firstly as a stonemason after which he was articled to an architect before moving to London where he set up a specialist construction supplies business partnership with Brett Elphicke, sometime a church architect.