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Have a look at the Geogebra animation below (the play button is in the bottom left corner) and try to figure out how the construction works. The player must first pocket a red ball and then try to pocket any colour he may choose, scoring the value of the ball that he has pocketed. The first ball must be placed at the apex position (front of the rack and so the center of that ball is directly over the table's foot spot). An easy way to remember these positions is with the mnemonic, 'God Bless You', with the first letter of each word being the first letter of the three colours as they are racked from left to right on the baulk line. In nine-ball games where a handicap is given by one player being spotted a ball, some tournament venues enforce a rule that the spotted ball must be racked as one of the two balls in the row directly behind the 1 ball. At that time, the fourteen pocketed balls are racked with no apex ball, and the rack is so placed so that if the apex ball were in the rack, its center would rest directly over the table's foot spot.

In carom billiards games, when all the balls are kept near each other and a cushion so that with very soft shots the balls can be "nursed" down a rail, allowing multiple successful shots that effectively replicate the same ball setup so that the nurse shots can be continued almost indefinitely, unless a limit is imposed by the rules. I’m writing a passage about Morgan Earp who became obsessed with billiards in his late twenties. Most of the time carom balls are not numbered. Coloured ball racking positions must be remembered with care, as each time a coloured ball is potted, it is immediately replaced to its starting position, which occurs multiple times per frame, what is billiards whereas reds are not returned to the table's surface after being potted. The rules also vary depending on whether the cue ball or fifteenth ball are resting on the table's head spot. Such rules are detailed on the following chart (note therein that the kitchen refers to the area behind the table's head string).

A semicircle of radius 11.5 inches, called the "D", is drawn behind this line, centred on the middle of the line. Further up the table is the pink ball, which sits midway between the blue spot and the top cushion, followed by the red balls (one each), placed in a tightly-packed triangle behind the pink. Adolph Noé developed a method of peeling coal balls using nitrocellulose. Membrane filters made of a mesh of nitrocellulose threads with various porosities are used in laboratory procedures for particle retention and cell capture in liquid or gaseous solutions and, reversely, obtaining particle-free filtrates. Collodion, a solution of nitrocellulose, is used today in topical skin applications, such as liquid skin and in the application of salicylic acid, the active ingredient in Compound W wart remover. In 1832 Henri Braconnot discovered that nitric acid, when combined with starch or wood fibers, would produce a lightweight combustible explosive material, which he named xyloïdine. Guncotton, dissolved at about 25% in acetone, forms a lacquer used in preliminary stages of wood finishing to develop a hard finish with a deep lustre.

Nitrocellulose (also known as cellulose nitrate, flash paper, flash cotton, guncotton, pyroxylin and flash string, depending on form) is a highly flammable compound formed by nitrating cellulose through exposure to a mixture of nitric acid and sulfuric acid. The yields are about 85%, with losses attributed to complete oxidation of the cellulose to oxalic acid. The process uses a mixture of nitric acid and sulfuric acid to convert cellulose into nitrocellulose. In precise chemical terms, nitrocellulose is not a nitro compound, but a nitrate ester. The glucose repeat unit (anhydroglucose) within the cellulose chain has three OH groups, each of which can form a nitrate ester. In the form of collodion it was also a critical component in an early photographic emulsion, the use of which revolutionized photography in the 1860s. In the 20th century it was adapted to automobile lacquer and adhesives. This was used commercially as "celluloid", a highly flammable plastic that until the mid-20th century formed the basis for lacquers and photographic film. In terms of lacquers and coatings, nitrocellulose dissolves readily in organic solvents, which upon evaporation leave a colorless, transparent, flexible film. Nitrocellulose is widely used as support in diagnostic tests where antigen-antibody binding occurs; e.g., pregnancy tests, U-albumin tests, and CRP tests.