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THE POPULAR SCIENCE MONTHLY.

of that common reverence for the past, and for the unexplainable, which not only unconsciously augments the actual, but revolts at the reduction of these works to the level of the existing red-man.

WRITING PHYSIOLOGICALLY CONSIDERED.

By CARL VOGT.

MODERN investigations have shown us that certain parts of the brain, situated in the region of the temples, have a predominant share in the formation of articulate language; or, to express it in a short phrase, that the majority of men speak by means of the third frontal circumvolution of the left cerebral hemisphere. All who have occupied themselves a little with physiology know also that the nervous fibers cross each other in the brain, so that the movements of the left arm are commanded by the right hemisphere, while those of the right arm depend on the left hemisphere. Rushes of blood, extravasations, and apoplexies are unfortunately more frequent on the left side than on the right side of the brain: attacks of the left hemisphere are consequently followed by paralysis of the right limbs, and aphasia, or an impossibility to speak; bat injuries to the right hemisphere, while they paralyze the left limbs, generally leave language untouched.

Does this center exist for writing as well as for language? Inasmuch as we are in the habit of writing with the right hand, it is evident that the movements necessary for the action of writing must be paralyzed by an affection of the left hemisphere. But we may learn to write with the left hand. The question, we see, becomes general; it extends to the general movements in writing, and is concentrated at last in a single point: are there facts which force us to admit a particular cerebral center, on which the movements in writing depend? In other words, does the manner in which we write depend upon a physiological necessity—determined by the structure of the brain? All peoples write with the right hand. It is of little importance whether this preponderance of the right is founded on a particular structure, or whether it is in great part the result of education and habit; man, writing with the right hand, writes therefore under the direction of the left cerebral hemisphere.

If this is a general fact, and I know of no exception to it, we may ask how it happens that the arrangement of the letters and the lines is so different among different peoples. The peoples of Eastern Asia, as a rule, arrange their letters from above down, and the lines from right to left; the Shemites and the Europeans put the lines one below another, but the Shemites arrange their letters from right to left, while the Aryans arrange theirs from left to right. The Shemites have centripetal writing, the Aryans have centrifugal writing.