This subject was touched on recently and has had brief mentions before, perhaps time to give a bit more history for those interested....
Many mower manufacturers sold carriages for transporting lawn mowers to make life easier and avoid damage to the machines when moving across hard surfaces.
Certainly Atco, Greens, JP, Ransomes & Webb transporting wheels or carriages have been seen.
Thomas Green & son patented their 'Lawn Mower Carrier' in 1894 with one shown in the image that could take an 18in to 24in mower, (1870's 20in Silens Messor pictured) the wheels being cast & fairly small would perhaps only be of assistance on extremely flat hard surfaces, they did probably use them also for moving mowers around in the factory.
Ransomes advertised their carriages in the 1890's, as with Greens even accommodating an 8in mower
Atco patented carrier wheels for the Standard in 1928, a pair to fit a 14in mower shown below
The Webb wheels seen fitted to the Witch & Deluxe have always amused me as for many the mower can be carried in one hand! The wheels could remain attached to the mower when cutting, & simply hinged down when crossing the drive, paths etc
In more recent years fine turf mowers like the Certes had the option of wheels to prevent damage to the aluminium roller when moving over hard surfaces.
I hope the above is of interest, carrier wheels are not that common & yet another item the serious collector can add to their collection, & also make life easier when moving your mower.