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.
Brass is an alloy of copper and zinc. It's used to make musical instruments, coins, works of art and household fixtures such as doorknobs and faucets. There are several different types of brass. Pewter is an alloy of tin and another metal, such as antimony, silver, lead or bismuth. It is used for household items such as flatware, drinking vessels, buttons and candlesticks. Pure gold is too soft for everyday wear, so it's alloyed with other metals to make it stronger while retaining its beauty.