The words âat least 17 years of age and *â*â* under 45 years of ageâ are substituted for the words âwho shall be more than seventeen years of age and *â*â* not more than forty-five years of ageâ.
Steel is cheaper, and brass is more expensive, and not much of a structural material. Brass is a tensile metal, and has a great ability to bend. It is used to make bearings, valves and moving parts, because it does not break easily. Steel, on the contrary, is difficult to cast, and quite difficult to work with in small machines.
Both are alloys and both contain a lot of copper - but that is where the similarities end. Comparatively, brass is a very soft metal. For example, it is used for plumbing fixtures because it is easy to work with and easily tooled. Brass is not as hard as bronze. Brass is also prone to corrosion, so most plumbing fixtures are coated with another metal such as chrome to make it more durable. You will find that a brass bell does not sound as pure as a bronze bell. Brass bells have kind of a clangy or brassy sound to them. Bronze on the other hand is very hard and can last forever. In fact, there are several grades of bronze. A type called admiralty bronze was used for cannons and is used for propellers on boats. Bell Bronze is the purest type of bronze in the bronze family.