The appellant, Manuel Garcia, was the plaintiff in the trial court where he suffered an adverse jury verdict on his complaint charging the Jarvis Corporation, the defendant-appellee, with negligence in the manufacture of a pneumatic saw purchased by Garcia’s employer. The single point raised on this appeal is:

“Did the trial court err by not permitting testimony as to the purpose and effect of alterations and modifications to the subject saw?”

Our review of the record in the light of the briefs and oral argument does not disclose the error claimed. The judgment is affirmed upon authority of the rule stated in Florida Power Corporation v. Willis, 112 So.2d 15, 20 (Fla. 1st DCA 1959):

“It is a sound rule that when physical situations or matters of common knowledge point so certainly to the truth as to leave no room for a contrary determination, based on reason and common sense, such physical situation and reasonable probabilities are not affected by sworn testimony which, in mere words, conflicts therewith.”

Affirmed.

SCHWARTZ, J., concurs in conclusion.