À DR. THOMAS STERRY HUNT ON THE 
When we have attained to this conception of hylozoism, of a living material universe, 
the mystery of Nature is solved. The Cosmos is not, as some would have it, a vast ma- 
chine wound up and set in motion with the certainty that it will run down like a clock, 
and arrive at a period of stagnation and death. The modern theory of thermodynamic, 
though perhaps true within its limitations, has not yet grasped the problem of the uni- 
verse. The force that originated and impelled, sustains, and is the Divine Spirit, which 
“ Lives through all life, extends through all extent, 
Spreads undivided, operates unspent.” 
The law of birth, growth and decay, of endless change and perpetual renewal, is 
everywhere seen working throughout the Cosmos, in nebula, in world and in sun, as in 
rock, in herb and in man; all of which are but passing phases in the endless circulation 
of the universe, in that perpetual new birth which we call Nature. This, it will be said, 
is the poet’s view of the external world, but it is at the same time the one which seems to 
me to be forced upon us as the highest generalization of modern science. 
The study of Nature in its details presents itself to the mind in a two-fold aspect,—as 
historical and as philosophical. The first of these gives rise to a General Physiography or 
description of nature, which we commonly call Natural History as applied to each of the 
three great divisions designated as the mineral, vegetable and animal kingdoms. This 
physiographic method of study in the latter two gives us systematic and descriptive 
botany and zoology, with their classifications and their terminology ; while the physio- 
graphy of the mineral kingdom includes not only systematic and descriptive mineralogy, 
as generally understood, but those branches of geology which we designate as petrography 
and geognosy, or the study of the constituents of the earth’s crust, their aggregation and 
their distribution. 
The second aspect of the study of nature, which we have designated as philosophical, 
regards the logic of nature, or what the older writers spoke of as General Physiology. 
This is sometimes appropriately termed Natural Philosophy, a designation which is the 
correlative of Natural History. With this method of study in the organic kingdoms we 
are familiar under the names of physiological botany and physiological zoology, which 
concern themselves with anatomy, organography, and morphology, and with the processes 
of growth, nutrition and decay in organized existences. The natural philosophy of the 
inorganic world investigates the motions and the energies of the heavenly bodies, and 
then, coming down to our planet, considers all the phenomena which come under the head 
of dynamic or physic, as well as those of chemistry. These various activities together 
“constitute the secular life of our planet. They are the geogenic agencies which in the 
course of ages have moulded the mineral mass of the earth, and from primeval chaos have 
evolved its present order, formed its various rocks, filled the veins in its crust with metals, 
ores, gems and spars, and determined the composition of its waters and its atmosphere. They 
still regulate alike the terrestrial, the oceanic and the aérial circulation, and preside over the 
constant change and decay by which the surface of the earth is incessantly renewed, and 
the conditions necessary to organic life are maintained.” * Thus the physiological study 

*The Domain of Physiology, or Nature in Thought and Language, by T. Sterry Hunt; London, Edinburgh 
and Dublin Philosophical Magazine ([V.] xii. 233-253) for October, 1881. Also, separately published by $. E. 
Cassino, Boston, 1882. 
