MAGNOLIA (Nco-Lat., named in honor of Pierre Magnol, a French botanist of the early seventeenth century). A genus of large-leaved beautiful trees of the natural order Magnoliacelp, with large solitary flowers, having a calyx of three sepals, a corolla of six to twelve petals, and carpels arranged in cones. The species are natives chiefly of North America, the Himalaya Mountains, China, and .Japan. The wood is in general soft. spongy, and of little value. Mag nolia grandiflora, sometimes called the big laurel, is a lofty and magnificent evergreen, rendered conspicuous at a great distance by its white flowers sometimes a foot in diameter. It is found in the lower districts from North Carolina to the Gulf of Mexico. Magnolia. Umbrella is found on the Alleghany Mountains, and extends as far north as latitude 43°. From the radiated manner in which its leaves are disposed at the extremities of the branches, it is called umbrella tree. It has very large white flowers. Magnolia
acuminata, cucumber tree, inhabits the same districts, and is a lofty tree with greenish-yellow flowers, which are less admired than those of mined with the theodolite, which is then replaced on the mounting by the magnetometer. The read er can find full descriptions of magnetometers in the Bulletins of the Division of Terrestrial Mag netism of the United States Coast and Geodetic Survey and in the issues of Terrestrial Magnetism (Baltimore, current). The older forms of mag netic instruments will be found described in the larger treatises on physics, while the simple ap paratus is discussed briefly in Thompson, Ele mentary Lessons in Electricity and Magnetism (enlarged ed., New York, I901).