Might this compact surface grinder - offered both for bench mounting and compete on a heavy cast-iron stand -  have been manufactured by the Delta Company before they were sold to Rockwell in 1945. The founder of Delta was Herbert Tautz, so might the Tauco brand be a play on his surname? However, cast into the body of some versions is "Milwaukee Toolmaker Grinder" with the (easily-changed) wheel cover badged as "Tauco" and others with others just marked "Delta-Milwaukee Toolmaker Grinder". Some wheel guards (presumably early ones) carry a Tauco badge, others merely an arrow indicating the anti-clockwise direction of rotation with a small circular Delta badge at the motor end of the casting..
With two spindle speeds driven by a V-belt running over pulleys drilled with holes to balance them, the head assembly was balanced by the motor - this arrangement removing any backlash. Quick setting of the head was by a course wheel that turned a long keyed shaft, this arrangement being combined with a fine down feed via the rotation of the whole head controlled by a plastic handwheel with a micrometer dial graduated at intervals of 0.001". The current owner reports that the system works well, with the coarse adjustment set and clamped quickly followed by the fine setting. His machine is engraved with the serial number "34-4340", might this be decoded as an indication of a manufacturing date as early as 1934?
The last model manufactured was branded as the Rockwell Delta and, though it used the same design principles, had its controls rearranged; an example can be seen towards the bottom of this page.
Keen to protect the design, Tauco-Delta patented the machine not only in the United States but also in a rather odd mixture of countries: Australia, Brazil, Canada and the United Kingdom.
One of only a handful of dedicated, smaller surface grinders made worldwide that could be bench mounted, the Delta-Tauco joined the lovely American Sanford, the
English Herbert pre-WW2 "Ball-bearing Bench Surface & Die Grinder" (and later a floor-mounted hand-operated model), and the English EXE their very fine bench and stand-mounted machine. A French Company, Lipemec, produced the beautiful LIP 515, this having the same capacity as the Sanford SG-48 at 8" x 4" (200 x 100 mm), a somewhat similar base, saddle and table but with a completely different, double-column upright to carry the grinding head - the solid steel bars being hardened, ground and protected by bellows. Grenby, an American machine maker better known for their cylindrical grinders, offered a slightly larger table-top unit, the design (in a modified form) being used as the basis for the Australian Macson. From Taiwan came the Richyoung and, in recent years, a version of the "Grenby-Macson" has been produced in China to be sold under various brand names including Harbor Freight and Tormach. The Tormach, manufactured to a higher level of accuracy and finish is, today, available with automatic feeds and has travels of 6 by 12 inches - those for the hand-feed Grenby are not known. Another example is the very high quality, superbly constructed unit from the Swiss Bulova watchmaking company - though this model might be considered too large and heavy for the descriptions "smaller" or "miniature" to be applied.
Other hand-operated surface grinders include the 2B and 2LB Brown & Sharpe models, the Capco,  Eagle,  Superior,  Feinprüf,  Jones & Shipman Model 540H and  Norton Model TS. The Builders Iron Foundry in Providence, Rhode Island, manufactured a simple, fairly crude table type with a hand-lever feed - and it appears that this pre-dates all the others, though no details are presently known. If you have one, or any information about it, the writer would be delighted to know.