Half Hours With Modern Scientists: Lectures and Essays

The title of this Series of Essays—_Half Hours with Modern Scientists_—suggests a variety of thoughts, some of which may not be inappropriate for a brief introduction to a new e...

In physiological language this means, that all the multifarious and complicated activities of man are comprehensible under three categories. Either they are immediately directed...

But it will be observed, that the existence of the matter of life depends on the preëxistence of certain compounds, namely, carbonic acid, water, and ammonia. Withdraw any one o...

In the Syracusan Poecile, says Alexander von Humboldt in his beautiful little allegory of the Rhodian Genius, hung a painting, which, for full a century, had continued to attrac...

The heat which is produced by the living body is obviously of the same nature as heat from any other source; it is recognized by the same tests, and may be applied for the same...

Assuming the density of the earth to be 5·5, its weight would be 6,500,000,000,000,000,000,000 tons, and its impact—by the formula given above—would be 1,025,000,000,000,000,000...

On the first head, for example, or as regards faculty, power, the action exhibited, there are but three categories of _human_ activity—contractility, alimentation, and reproduct...

What now of the unities of form and power in protoplasm? By form, Mr. Huxley will be found to mean the general appearance and structure; and by faculty or power, the action exhi...

The whole former part of Mr. Huxley’s essay consists (as said) of fifty paragraphs, and the argument immediately concerned is confined to the latter ten of them. This argument i...

But, in the middle of it, as we have seen, Mr. Huxley concedes that these manifestations are differently known to the subject of them. If so, what becomes of his assertion of bu...

Neither molecularists nor Darwinians, then, are able to level out the difference between organic and inorganic, or between genera and genera or species and species. The differen...

Such regularity of plan is found to exist in the relations of the great divisions of the animal and vegetable kingdoms as at present existing on the earth. Thus, with animals we...

In a word, we learn from this source that distinct geologic epochs coexist at the same time on the earth. I have been forced to this conclusion[47] by a study of the structure o...

It is infinitely improbable that a being endowed with such capacities for gradual progress as man has exhibited, should have been full fledged in accomplishments at the moment w...

Thus we have two terms to start with in estimating the beginning of human development in knowledge and power: First, the primary capacities of the human mind itself; second, a m...

That their condition was evil must be fully believed if they were condemned by the executive of the Jewish law. This law, it will be remembered, permitted polygamy, slavery, rev...

Side by side with the mathematical method, we have the method of experiment. Here, from a starting-point furnished by his own researches or those of others, the investigator pro...

For a long time I was troubled by the appearance there of floating dust, which, though invisible in diffuse daylight, was at once revealed by a powerfully condensed beam. Two tu...

In Goethe, so glorious otherwise, I chiefly noticed the self-inflicted hurts of genius, as it broke itself in vain against the philosophy of Newton. For a time Mr. Bain became m...

And now I would ask your imagination to picture this act of reflection. What must become of the reflected light? The atmospheric layers turn their convex surfaces towards the su...

Similar arguments have been used by the opponents of the germ theory of epidemic disease, and both parties have triumphantly challenged an appeal to the microscope and the chemi...

I have thus led you to the outer rim of speculative science, for beyond the nebula scientific thought has never ventured hitherto, and have tried to state that which I considere...