Grooving

(noun.) the cutting of spiral grooves on the inside of the barrel of a firearm.

校对:马特

• This covered broadly the combination of the cutting cylinders, and rolls for holding the boards against the cutting cylinders, and also means for tongueing and grooving at one operation. Edward W. Byrn. 十九世纪发明进展.

整理:朱莉安娜