¹ The “data” furnished by a legislative reference bureau are of course only such as may be yielded by material in print, i.e., secondary sources. They are not sought in the field or laboratory as are the data sought by an investigating commission, such as that on industrial relations. A legislative reference bureau undertaking original investigations of this latter sort—e.g., by taking testimony or canvassing for mere opinion—runs the peril of two criticisms: (1) of embarking in projects for which it is not equipped and (2) of promoting mere partisanship.