Mass. Gen. Laws ch. 127, § 116: Application of original sentence of prisoner removed or returned

Section 116. A prisoner who is removed or returned under any provision of sections ninety-seven to one hundred and fifteen, inclusive, shall be held in the place of imprisonment to which he is so removed or returned under the terms of his original sentence, unless sooner discharged, and the period for which he is so removed shall be reckoned as a part of the term of his imprisonment.