Decree affirmed. This is an appeal from a final decree of the Superior Court annulling a decision of the board of appeal of the city of Lowell which granted a special permit for the addition of a building to what had been a preexisting nonconforming use. The trial judge ruled that “the absence of any standards in . . . [the material section] of the by-law is fatal and the by-law in effect is an unlimited delegation of the zoning power to the Board of Appeal.” We agree. We see no need for repeating the legal principle which was correctly stated by the *793trial judge. Chilson v. Zoning Bd. of Appeal of Attleboro, 344 Mass. 406, 413. Clark v. Board of Appeals of Newbury, ante, 407, 408-409.