The above are in inches and decimals.
Measure-angle, a brass instrument to measure angles, either saliant or rentrant, for exactly ascertaining the number of degrees and minutes, to delineate them on paper.
| MEASURING, | - | |
| MENSURATION, |
in military mathematics, the assuming any certain quantity, and expressing the proportion of other similar quantities to the same; or the determining, by a certain known measure, the precise extent, quantity, or capacity of any thing.
Measuring, in general, constitutes the practical part of geometry; and from the various subjects which it embraces, it acquires various names, and constitutes various arts, viz.
[Longimetry], [Altimetry], [Levelling], [Geodesia], or [Surveying], [Stereometry], [Superficies], and [Solids], &c. which see.
Measuring. See [Chain].
MECHANICS, a mixed mathematical science, which considers motion and moving powers, their nature and laws, with the effects thereof, in machines, &c. The word is derived from the Greek. That part which considers motion arising from gravity, is sometimes called statics, in contradistinction from that part which considers the mechanical powers and their application, properly called mechanics: it is, in fine, the geometry of motion.
Mechanics. The whole momentum or quantity of force of a moving body, is the result of the quantity of matter, multiplied by the velocity with which it is moved; and when the product arising from the multiplication of the particular quantities of matter in any two bodies, by their respective velocities are equal, their momentum will be so too. Upon this easy principle depends the whole of mechanics; and it holds universally true, that when two bodies are suspended on any machine, so as to act contrary to each other; if the machine be put in motion, and the perpendicular ascent of one body multiplied into its weight, be equal to the perpendicular descent of the other, multiplied into its weight, those bodies, how unequal soever in their weights, will balance each other in all situations: for, as the whole ascent of the one is performed in the same time as the whole descent of the other, their respective velocities must be as the spaces they move through; and the excess of weight in one is compensated by the excess of velocity in the other. Upon this principle it is easy to compute the power of any engine, either simple or compound; for it is only finding how much swifter the power moves than the weight does, (i. e. how much further in the same time,) and just so much is the power increased by the help of the engine.
The simple machines usually called mechanic powers, are six in number, viz. the lever, the wheel and axle, the pulley, the inclined plane, the wedge, and the screw.