American Levels and Their Makers
Some time in the early 1880s, the Davis Level & Tool Co. of Springfield, Mass. introduced their first cast iron carpenters' level. It is known as the spindle form for obvious reasons. This design was patented by Leonard Davis in 1877 and the adjustment mechanisms for the level and plumb fixtures were patented by him in 1883. But, like many of his other inventions, it was apparently produced for some time before the patent for the adjustment was issued. It was most probably produced even before Davis applied for that patent. The spindle form of the level was sold in 6", 12", 18" and 24" lengths (as were the other forms) and is quite rare. The more recognizable form of the Davis carpenters' level, which was introduced later, incorporates much fine filigree between the top and bottom rails.
The manufacture of this form of the level differed from the normal Davis procedures in that it had a base coat of yellow paint whereas the early Davis procedures utilized a black japanning with gold trim and the later procedures utilized only black japanning. The yellow base coat was covered with black japanning but the japanning did not adhere well to the base and consequently most examples of these levels appear to be mostly yellow.