Page:Popular Science Monthly Volume 3.djvu/315

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303
ON ACQUIRED PSYCHICAL HABITS.

conditions have to be considered that no standard can be laid down beyond the broad fact already stated—that one-sixth of the coal we commonly now use would suffice for all our requirements if it were properly utilized. I do not, however, anticipate that much progress will be made in economy, unless the price of coals should remain at a figure which will induce the householder to make himself thoroughly acquainted with the principles on which the apparatus for warming and cooking should be constructed and worked; for there is no apparatus which can be invented which will not depend, to a considerable extent, on the manner in which it is attended to.

The principal conditions which I have enumerated have long been known. There is an old saying in South Staffordshire, that "he who lives longest must carry coal farthest," and, acting on this, we have, year after year, simply wasted millions of tons of coal in our domestic fireplaces, because the coal was provided at a small cost, and we have had no thought for posterity.

George Stephenson once said, very happily, that coal represented the accumulated rays of the sun laid up in store in by-gone days. When this store is gone, the world will have lost the most convenient and economical means of generating heat. It is, therefore, a duty, which every man owes to posterity, to do his utmost to husband this great store.

I have endeavored to do my part by explaining the conditions which should govern the arrangements devised for regulating the consumption of fuel for domestic purposes. It remains for the public to insist on having these principles applied to the various apparatus which they adopt.—Journal of the Society of Arts.

 

ON THE HEREDITARY TRANSMISSION OF ACQUIRED PSYCHICAL HABITS.
By Dr. WILLIAM B. CARPENTER, LL. D., F. R. S.

PROCEEDING, now, to show that the tendency of modern Physiology is to prove the existence of a distinct causal relation between Physical changes in the Nervous System and definite modes of Mental action, it may be well for me to adduce, in limine, the positive evidence that all Mental activity is dependent on a Chemical reaction between the Blood and the Brain: for, although this is one of the best-established facts in Physiology, it is, I believe, taken very little account of by Metaphysicians.—The Brain is supplied with Blood by four Arterial trunks, which enter the cranial cavity at no great distance from one another, and then unite into the "Circle of Willis;"