Mass. Gen. Laws ch. 98, § 4

The state standards shall also include all weighing and measuring devices received from the United States under the resolution of congress approved June fourteenth, eighteen hundred and thirty-six, and all other weighing and measuring devices received from the United States as standard weights and measures, and such as have been or shall be supplied by the commonwealth and certified by the national bureau of standards. Weighing and measuring devices procured to replace the standards shall be preserved in the same form and of the same dimensions as required of said standards, and the denominations thereof shall be marked thereon.