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Last, not least, Dr. John Lindley, who had scarcely left his cradle when Sir William Hooker's botanical career commenced, only survived him a few weeks. He also was born in Norfolk, a coutny famous for the production of excellent botanists, in the year 1799. At the age of twenty he published a translation of a French work on fruit, and the next year appeared his first original production, a Monograph of Roses. He assisted Loudon with his "Encyclopædia of Plants;" produced a great monument for himself in his "Vegetable Kingdom;" was for a quarter of a century Professor of Botany at University College; wrote the majority of botanical articles for the "Penny Cyclopædia;" and was for many years associated with the Botanical Register and the Gardener's Chronicle. Besides this he was doubtless our best special authority for orchidaceous plants.

It is impossible to estimate the influence of these two men on botanical science in this country during half a century. If we endeavour to compare what it was under the old Linnæan system, when they each began the study of plants, with what it is when both have but just disappeared, we shall be astonished at the changes, in which each performed his share of the work.

It will be long ere the eventful year now fast drawing to a close will be forgotten. This year, which deprived America of its President and Britain of its Premier; Russia of its Czarevitch and Rome of its Anglican Cardinal, will be remembered through many generations. But to men of science in England it will be remembered as the year which robbed them of some of their noblest veterans; to botanists especially as that in which Hooker and Lindley died. "Peace to the sould of the heroes departed." They have left us for a land where, not only "the wicked," but the minor cares and anxieties of this life—

In these days, when the Microscope is becoming a valuable auxiliary in the education of the people, a few brief hints on the selection of an instrument by whose aid we pry into Nature's minutæ, may not be considered out of place in the pages of Science Gossip.

As the stability of a house depends on the stability of its foundations, so does lack of a microscope depends on similar qualities—the solidity and strength of its stand. The tripod, or three-footed stand, seems for all forms to be that most generally adopted by our best makers, and from which we may fairly conclude that it has recommended itself to their notice by its firmness and freedom from tremor. The feet of a tripod should be both broad and solid, so as to furnish a firm support or base to the pillars or cheeks resting thereon, and between which the whole optical part of the instrument, with its lenses, stage, substage, and illuminating apparatus, is suspended. And these portions of a microscope should be so well balanced, that the centre of gravity will not be materially disturbed, at whatever angle is optical part may be inclined. In a badly-constructed microscope there is often an tendency to tip over in some given direction whenever the body is inclined from a vertical to a horizontal position. And it is just as well to test this tendency before purchasing an instrument. In microscopes constructed with a single pillar resting on the centre of a round foot, this tendency is augmented, and such an instrument should be rejected as unstable. In working with the microscope, it is frequently necessary to inclune the body of the instrument for convenience of observation. To allow of such a motion, the optical portion must be attached to its pillars or supports by hinge or cradle joints, which enable the body to be inclined ninety degrees from the perpendicular. These should work, with just sufficient stiffness to retain the body of the microscope at whatever angle it may be placed. Where, however, the microscope is in daily use, the wear and tear will tend to loosen the joints; but the fault may be easily remedied by simply tightening the screws. In the majority of instruments the tube or body is firmly screwed into one end of an arm, while the other end is attached to a triangular bar, with a rack cut on one of its edges, in which works a pinion with two large milled heads. In the more modern instruments, the triangular is superseded by a square form of bar, having the rack-work on one of its sides. But I am not aware whether or not greater steadiness and smoothness of motion is gained by this mode of construction. Some makers prefer a stand in which the body of the microscope is supported along the greater portion of its length. In such a form the rack-work is attached to the body itself, and has two small flanges that work in grooves, ploughed out of the limb. By this contrivance the body is kept in contact with the arm that supports it, and on which it freely moves. This plan possesses the merits of simplicity and steadiness, but does not, as in the former plan, admit of the body being turned away from the stage, an advantage which is sometimes of use to the microscopist. Whatever, however, may be the mode of supporting the body, the rack and pinion should be accurately cut to fit each other; unless great nicety is here shown, we shall fail to obtain that smooth and even motion so necessary to securing the focus of a sensitive object-glass. A badly-cut rack may be known by its jerking uneven motion, which communicates a most disagreeable vibration to the whole instrument, and