William
Henry Brewer, 1826-1910
Norton's
student, William Henry Brewer, would take Norton’s lessons
into forestry in the late-nineteenth century. Like Norton, Brewer
migrated between the family’s agricultural pursuits and
their extensive aristocratic society. Brewer had many connections
in the scientific community, with whom he shared his growing
collections of mosses and minerals. [MOSSES] With the intent
of pursuing a scientific career, he first studied chemistry,
botany and geology at Ithaca Academy and in 1848 entered the
Yale Scientific Laboratory where he took Benjamin Silliman Jr’s
courses in chemistry and Norton’s in agricultural chemistry.
With his Yale credentials and the support of his personal and
scientific network, Brewer taught chemistry at Ithaca Academy
between 1850-1851, and at a venture Agricultural Institute in
Western N.Y. (His diaries from this period reveal that he enjoyed
a number of picnics organized by the women of the school [swing],
rare visits by his friends, but first and foremost his trip
to Niagara Falls.) In 1852 he received a Ph.D. from the Yale
Laboratory and secured a position teaching at physiology, natural
philosophy, and agricultural chemistry at Ovid Academy in N.Y.
These teaching positions failed, however, to satisfy Brewer.
Brewer never missed the forests for the trees—each played
essential part of his psyche and would do so throughout his
long life. In 1853, when contemplating the pros and cons of
a European apprenticeship, he took a long solitary walk in the
woods, set himself down under a tree and “as was his habit
fell in dreamy reveries.” “The wind was high, and
played among the treetops, hurrying past me, at every blast
clouds of leaves, dropping them to their annual grave. How like
us mortals. They rustle among the branches, then fall, and soon
mingle with the soil, WE flourish for a time, rustle among the
branches of society, then pass away to mingle with mother earth,
to be soon forgotten . . . .” Brewer’s poetic vision
represents the natural theological view that his and Norton’s
generation of agricultural scientists, codified into their laboratory
investigations.
Brewer finally took the insistent advice of the Sillimans and
his close friends who bombarded him with a steady stream of
enticing and cajoling letters from various European cities,
and in 1854 sailed to Germany. He had calculated that his planned
two-year investment would provide him the credentials that he
needed to secure a professorship. He studied chemistry first
with Bunsen’s excellent laboratory at Heidelberg and later
with Liebig much poorer facility at Giessen. Bunsen’s
chemical lectures bolstered the holistic vision Brewer had developed
in the U.S. From Bunsen’s lecture on “Air,”
for example, Brewer learned that living organisms played an
important role in maintaining the circulation of matter in nature.
In a holistic system that united the animal, plant and geological
realms, Bunsen taught that “The oxygen used up during
the decomposition of organic matter, during animal respiration,
and through absorption by rocks, is recompensed for the animal
world, by plants which decompose the CO2 given off from volcanoes.”
This was not merely a lesson in theory; with Bunsen, Brewer
conducted extensive analyses of organic matter to investigate
the role plants played at the juncture of the inorganic and
organic realms.
In 1869, Brewer drew on the cycle of life to explain the natural
history and recommend the proper management of pastures and
meadows—for him two agriculturally significant formations.
Here he tried to understand why old pastures that had not been
disturbed by the plow for many years were vastly superior to
those that were made recently. While climate might determine
the characteristics of the pastures, science and agriculture
pointed, Brewer wrote, to another important element—the
role of human beings in managing the soil. His holistic view
stands out in his discussion of proper soil management. If the
owner of the pasture wages war against the weeds and encourages
more desirable species of grasses, the cattle will eat off the
herbage and leave their droppings on the surface. Much of the
foliage also dies off each year mingling with the mere surface
soils and slowly but surely the vegetable matter increases there.
The annual crop is drawn largely from the air, and that which
is left on the ground does not go back to its original elements
quickly, and thus it is that the vegetable matter increases,
especially at the surface. The plants also help to bring the
mineral elements in the soil into the cycle by making them soluble,
and after the plants die and decay they make them available
to future growths.
To justify his evaluation of the importance of pastures in agriculture,
Brewer turned not to the Germans with whom he had studied, but
to the authority of the French agricultural and organic chemist
Jean Baptiste Boussingault. Brewer agreed with Boussingault
that the whole object in the best systems of animal husbandry,
is to make the earth produce the largest amount of organic matter
in a given time. This was an holistic approach based on the
recycling of “a heap of dung”—a resource so
important in Brewer’s opinion, that he thought it determined
the great phases of human progress and decline through history.
It explained, for example, the differences between the American
North and South. Moreover, it was an essential factor in creating
“permanent pastures” and beautifying the landscape,
in the furnishing of food for the present generation, and also
the promise of permanent wealth and prosperity of the future.
In 1904, in his last lectures to the Yale forestry school that
he had helped to found, Brewer discussed the topic of forest
physiography, bringing together the cycle of life with physical
geography. Just as he thought pastures could be made by “art”
so could forests. And, since, for him, the trees are the natural
expression of the soil, he approached the subject in the same
way. But where in 1869, he could resort to chemical laws to
describe the cycle of nutrients in nature, after the 1870s and
the work of several agricultural chemists who showed the biological
nature of decomposition and soil processes such as nitrification
and ammoniafication, he now described the cycle biologically.
At the end of his lecture—which coincided with the end
of his career, Brewer concluded by looking forward. The forests,
he said, have introduced us to another field too wild to discuss
[in his lecture] but currently under investigation—that
is, forest ecology. Ecology, he explained, is the study of organisms
and their relationship to each other, and their relationship
to the soil. It is to here—to ecology—that the numerous
sciences related to the concept of the cycle of life lead. But
that is a subject for future work.
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