The excretion of Bence-Jones' protein occupies a special position in the pathologic picture of the albuminurias. The Bence-Jones body is characterized by precipitation at a relatively low temperature (from 40 to 50 C.), followed by clearing of the solution if the heating is continued to 100 C.; on cooling the protein appears again.
By far the great majority of cases of Bence-Jones' proteinuria have been observed in association with multiple myeloma of the bone marrow. In a few instances the excretion of Bence-Jones' protein has been noticed in cases of invasion of the bone marrow by some other tumor.
The close association of this peculiar type of proteinuria with disease of the bone marrow gave rise to the question whether this body could be a product of the normal bone marrow. I therefore injected into rabbits an emulsion of cow's marrow, from which the fat had been removed by extraction