Mass. Gen. Laws ch. 223 § 43
Railroad cars and engines and street railway cars, in use and making regular passages on railroads or railways, and steamboats so in use upon water routes, shall not be attached upon mesne process unless the officer who makes the attachment has first demanded of the owners or managers thereof other property, upon which to make it, equal in value to the amount of the attachment, and such owners or managers have refused or neglected to comply with said demand; except that a steamboat so in use may be attached, if the attachment is made more than forty-eight hours before its fixed time of departure. Such attachment shall be void unless the officer certifies in his return that he has made such demand and that the owners or managers have refused or neglected to comply therewith.
Mass. Gen. Laws ch. 223, § 43