Phoenix Iron Works (Hartford, USA)
of Hartford, Connecticut
1834 Started by Levi Lincoln, and subsequently carried on by George S. Lincoln as George S. Lincoln and Co.
Later carried on by the Taylor & Fenn Co.
Produced a range of machine tools, including lathes, planing machines, drilling machines, gear cutting machines, milling machines, and presses.
Lincoln Milling Machines
It appears that Robbins and Lawrence went to Hartford to make Sharp's rifles, and proposed the use of form milling cutters in a lathe to machine components fixed to the cross slide, and that this led Francis A. Pratt, a foreman at the works, to develop the Lincoln milling machine. This type of milling machine came to be very widely used, and was made for decades by a number of firms. It was very similar in principle to a lathe, but with the spindle bearings being arranged to elevate. The first example was made in the early 1850s, and several were sold to Robbins and Lawrence in 1855. The first machines were actually built by Amos Whitney as a contractor.
Their next type of milling machine was the Lincoln Index milling machine, also designed by Pratt and built by Whitney. The spindle bearings were fixed in the headstock (i.e. non-elevating). The headstock could be moved relative to the workpiece in the X and Y planes. The workpiece was held in a vice or other fixture on top of a vertical cylindrical column which could be elevated. The column could also be rotated, and was supplied with an indexing (division) plate. Starting in 1861, numerous examples were supplied to the armoury of Samuel Colt.
The above information is taken from a 1909 article in the American Machinist [1]
Anither source[2] names Frederick Howe as the designer of the Index Milling Machine built at the Phoenix Iron Works.