The laboring-man, fatigued by the wearisome hod, takes his nooning in any sequestered spot; but his inactive brain requires not sleep to refresh it, for no task has been imposed upon it, and he needs but to rest his limbs in the pleasant shade. A too prolonged exertion is followed by muscular irregularities, cramps, exhaustion, and rheumatic incapacities, effects disagreeable enough, but generally of temporary duration, and with little or no permanent effect on the general constitution or on succeeding generations.
WHEN we enumerate the few great living botanists, the list must include Dr. Asa Gray, Fisher Professor of Natural History at Harvard University. To the average reader, this may not imply any great distinction, as a botanist is too commonly looked upon as merely one who can call plants by name. Making specimens and naming plants no more make a botanist than taking an altitude makes an astronomer.
It is not our purpose to show here the scope of botany, nor to consider its claims to an equal rank with other departments of science.
Suffice it to say that it affords exercise for the keenest observation and the most skilful diagnosis; that the closest reasoning, the most thoughtful weighing of evidence, the acutest application of the logic of facts, in short, those qualities of mind that are required in any other scientific pursuit, are demanded of one who would take a high rank as a botanist. We would not be understood as speaking disparagingly of the humbler laborers in botany, for each one in his way does something for the general good. In all sciences the units are accumulated by patient workers whose isolated facts seem to have but little importance of themselves, but, when brought by some master-mind into relation with other facts, they often prove to be the missing links to a heretofore incomplete chain.
Prof. Gray was born at Paris, Oneida County, New York, November 18, 1810, and took the degree of M. D. at Fairfield College in 1831, but relinquished the medical profession for the purpose of prosecuting the study of botany. He was appointed botanist to the United States Exploring Expedition, in 1834, but, in consequence of the delay of that enterprise, resigned his post in 1837. He was elected Professor of Botany in the University of Michigan, but, before that institution went into operation, he took the position of Fisher Professor of Natural History in Harvard University, in 1842, where he now is.
One of the earliest if not the very first contribution of Dr. Gray to botanical literature is his "North American Gramineæ and Cyperaceæ." Two volumes of this were published in 1834-35, each containing a hundred species, illustrated by dried specimens. Several new species