Geo Plant & Son were based in Birmingham, one of the hundreds of similar small companies from that great industrial city whose records are now lost. While appearing almost toy-like, the great advantage a hand-operated planer such as the one shown below - and from around 1850 until the 1930s were very popular - is their ability to take long cuts that would otherwise require the use of a massive shaper or much tedious hand filing. In a small space, one has a highly versatile machine that takes inexpensive tooling - and needs no motor to operate. Happily, today, they are still greatly appreciated - even the larger, floor-standing types - and fetch corresponding high prices. Numbers of small planers have been found lacking any maker's mark, but known examples that become available from time to time in the UK include the Hesketh-Walker, Tom Senior, Britannia, Brittain, Selig Sonnenthal, T.Taylor, Milnes - and even some recently home-made models including the well-constructed Wilson. 
Typical of its kind, the Geo. Plant weighs around 120 lbs and has a bed seventeen inches long and six inches wide - though there is a little over seven inches available between the stanchions - these being secured to the bed by two bolts and aligned by a dowel. Longitudinal travel is, for a tiny machine, a useful twelve inches with the tool slide having a useable range of around three inches without the need to fit an excessively long bit - but can be used, practically, over four inches if necessary. Cross travel, at four inches, easily covers the maximum seven-inch width of a workpiece. 
Table drive is unusual, being by chain, its front fitted an adjusting screw and top hat washer, the latter indicating, perhaps, a missing spring.
While all other threads are threads are square, that on the gantry cross-slide screw is a 10 t.p.i. Whitworth-form pitch - but this could easily be - and probably was - a later modification. Further evidence is that, while marked on its the face with 100 divisions labelled every 10, the periphery of the screw's micrometer dial is divided into 64 - a figure that suits an eight t.p.i screw better, with 4 divisions equalling 1/128" - a setting handy for an operator used to working in fractions. A rather fine touch is the inclusion of a beautifully inlaid brass scale for setting the angle of the tool slide.
With a ratchet mechanism for the cross feed having 20 teeth that gives a 5-thou advance per stroke, the surface finish possible at that rate is, at least, reasonable. While the pawl flips over to allow rewinding by hand, it does not give a feed in the opposite direction - and the vertical bar clamp currently fitted is possibly not original. The rear face of the table has two tapped holes, these perhaps being intended to hold an end plate used to align a job - however, as the thrust is, of course, in the opposite direction, there may have been, originally, some similar provision made at the other end.
At some point in the past the tool clapper acquired a return spring - a now-uncommon flat clock type hinting that the modification was done some considerable time ago. Regrettably, fitting the spring damaged the maker's name stamp - but it does show that, at one time, the planer was in serious use rather than being relegated to the status of an interesting display object..