We pass the question whether par. 20 of the defendant's answer was sufficient to raise the affirmative defence of novation (see Mass. R.Civ.P. 8[c], 365 Mass. 750) because the undisputed facts set out in pars. 7, 11 and 15 through 17 of the defendant's answers to interrogatories and in his affidavit in opposition to the motion for summary judgment are insufficient as matter of law to warrant a finding that the plaintiff discharged the defendant from any existing liability to it. See Traveler Shoe Co. v. Koch, 216 Mass. 412, 415 (1914); Kirtley v. C.G. Galbo Co., 244 Mass. 179, 182-183 (1923); Larson v. Jeffrey-Nichols Motor Co., 279 Mass. 362, 365-366 (1932); Tudor Press, Inc. v. University Distrib. Co., 292 Mass. 339, 341 (1935); Harvard Elec. Mach. Co. v. G K Provision Co., 333 Mass. 678, 682-683 (1956).
Judgment affirmed.