In public billiard rooms only skilled players were initially allowed to use the billiards stick, because the fragile cloth could be torn by novices. The pool cue is a huge part of the sport. François Mingaud was studying the game of billiards while being held in Paris as a political prisoner, and experimented with a leather billiards cue tip. He called it “twisting powder”, and the magical impression this gave the public enabled him to sell it for a higher price than if they realized it was simply chalk in a small box. “English”, an American term for sidespin, derives from the British discovery of sidespin’s effects, as “massé” comes from the French word for “mace”. A second type is the two-piece snooker stick, divided in the middle for ease of transport, usually in a pool stick case. Some standard-sized break billiards cues include a two-piece butt allowing a player to remove the lower, heavier half of the butt to produce a jump billiards cue; these are usually referred to as jump–break or break–jump billiards cues. A high quality two-piece snooker cue with a nearly invisible wood-to-wood joint, so that it looks like a cheap one-piece house pool cue, is called a sneaky pete. Shafts are made with various tapers, the two most common being the pro taper and the European taper. Leather tips of varying curvature and degrees of hardness are glued to or in some cases screwed into the ferrule. Without proper care, the surface of the tip can develop an undesired smoothness or glossiness which can significantly reduce the desired friction between the tip and the pool cue ball. Harder tips major brands include Blue Diamond Plus, Triangle and Le Professional or “Le Pro” maintain their shape much better, but because of their hardness, chalk tends to not hold as well as it does on softer tips. The hardness of a leather tip is determined from its compression and tanning during the manufacturing process. One-piece tips are not subject to this problem, but they do tend to mushroom more easily.