cypress, the former of which he says is the more valuable for strength
and durability, owing to its being impregnated with resin. He also
observes that the "cypress knees," as they are commonly called, never
reach a height greater than the high water mark. In combating the
theory of Dupratz that the cypress is propagated from its root, Dunbar
says that is "invariably propagated from the seed, which is about
the size of a Spanish walnut," and that he has "often observed half
a dozen or more young plants produced from one apple, which often
coalesce into one and sometimes the greater part perish to make room
for their more fortunate brethren." He says of one species of the white
oak, that "nature has so ordained that the husk embraces the acorn so
firmly that they are not separated by their fall from the tree, by
which means this case by its comparatively small specific gravity buoys
up the acorn, and being carried along by the various current of the
inundation, serves to plant distant colonies of this species." He also
gives an interesting account of the cotton tree, the willow and the
bamboo cane, the last of which he attempts to classify botanically. He
says of the cane: "It produces a very abundant crop of grain, and that
only once, for it immediately after perishes, root and branch, it is
not known how many years the reed requires to arrive at this state of
maturity; if we were to suppose that 25 years were its limit, it must
happen that a person who has resided during that length of time in this
country and who has visited many parts of it must have seen all the
cane that came under his inspection once in grain, and upon the average
one twenty-fifth part of all the cane in a large tract of country
ought annually to yield a crop, but this is by no means the case, for
I who have lived during that length of time in this country and have
frequently traversed many extensive tracts of it, have never in any one
year seen 1-500 part of the canes in seed of those parts that I have
intimately known." He therefore concludes that it must require at least
five hundred years for this plant to reach "a state of maturity to
enable it to bear a crop of seed."
His description of the ornamental trees of this region is graphic and
interesting. No one can read his account of the magnolia tree without
being deeply impressed with the fact that he appreciated its beauty.
In studying the properties of the poplar, he made a hydrometer of a
thin, broad piece of plank of this material, cut across the grain. He
"improved its sensibility by boiling it when very dry, in a solution of
mild alkali or carbonated potash." He describes many other trees, among
which are the dogwood, the redbud, the wild cherry, the horse chestnut
and the sweet gum.
He records the observation of a very rare phenomenon, which he saw
August 12th, when engaged upon this work. It was a rainbow that
consisted of more than a semi-circle, "the vertical point" of which
"did not seem more than 8 feet from the eye, although the inferior
parts seemed farther removed, which produced an optical deception by
giving it the appearance of an ellipsis, the transverse diameter being
parallel to the horizon; this perhaps is the first natural rainbow
exceeding a semi-circle which has been seen by a human eye, because to
produce such an effect from the general idea formed of this phenomenon,
the sun ought to be in the horizon to cause the appearance of a full
semi-circle exceeded only by the parallactic angle of the elevation
of the eye above the base of the rainbow, which must generally be
insensible; the above effect however is easily accounted for on
Newton's principles[56] from the peculiar circumstances in which I was
placed."
He says that the microscope reveals in the water of this part of the
country the same varieties of animalculæ which he had often examined
in Europe and many new ones, which he does not remember to have seen
described by any writer, and which he hopes to find leisure to describe
at some future day.
After giving a brief account of some of the wild animals, reptiles,
fish, and birds of this country, he concludes with lists of the
"vegetable productions of the Swampy Grounds or such as are much
exposed to the Annual Inundation;" the "most remarkable vegetable
productions of the high lands;" and the "Trees and Plants cultivated
by the Inhabitants of the Mississippi territory and by those of the
adjoining Spanish Provinces."
As has been noted above, the last ten years of Dunbar's life were
devoted almost entirely to scientific research. The value of his
contributions to knowledge was widely recognized, and "The Forest"
became familiar to the scientific world, though it was sometimes
incorrectly placed in Louisiana.
Volume V. of the Transactions of the American Philosophical Society,
published in Philadelphia in 1801, contains three articles from his
pen, and Volume VI. of the same publication, issued eight years
later, contains twelve, one of which was translated into the German
and appeared in Gilbert's Annalen of Physics, vol. 31,[57] published
in Leipzig in 1809. To this latter volume of the Transactions Andrew
Ellicott contributed nine articles, Jose Joaquin de Ferrer, eight,
Dr. Benjamin Smith Barton, five, Benj. Henry Latrobe, three, and Dr.
Joseph Priestly, F. R. S., three, while to repeat Dunbar contributed
twelve. This shows that Dunbar was at that time one of the most active
investigators on the continent.
His contributions to the Transactions and his correspondence with
Jefferson give a conception of the character and extent to his
investigations. The first of these contributions was written June 30,
1800, and treats of the "Language of Signs among certain North American
Indians." In this he traces certain points of analogy "between the
Chinese written language and our Western language of signs." In both,
says he, there are certain "roots of language in which every other word
or species in a systematic sense is referred to its proper genus or
root." He gives, for example, the sign for water which is a genus and
shows that rain, snow, ice, hail, hoar-frost, dew, etc., are species
represented by signs more or less complex, retaining always the root or
genus as the basis of the compound sign. He adduces other interesting
facts from this study of the subject, which cannot be given in this
connection.
His Meteorological Observations for 1799, gives unmistakable evidence
of his devotion to science. It shows that three times a day, each day
in the year, he recorded the temperature and the barometric readings;
also the direction and strength of the winds with the state of the
weather, and the amount of rainfall together with remarks about
the state of the vegetation from time to time. To this he adds a
Recapitulation, giving the greatest, the lowest, and the mean points of
the thermometer and the barometer, and the amount of rainfall for each
month and then for the whole year. The Editor of the publication states
in a footnote that "the society have been induced to publish this
journal _entire_, as it is certainly the first that has been kept with
so much accuracy and attention in that part of the world, and may serve
as a standard with which to compare future observations."
In another article, Dunbar gives a "Description of a singular
phenomenon seen at Baton Rouge" in the spring of 1800.
His fourth contribution consists in extracts from a letter dated Aug.
22, 1801, which he wrote to Jefferson, relative "to fossil bones found
in Louisiana, and to Lunar Rainbows observed West of the Mississippi."
In this letter, he referred to an account of "Dr. Hooks' scheme of
a telegraphy, in the year 1684," which he intended to transmit to
Jefferson, but found himself anticipated in that communication by a
paper in the first volume of the London Philosophical Magazine. He also
directs Jefferson's attention to "a certain phenomenon at sunset,"--the
yellow orange color of the Eastern clouds, which ascends as the sun
descends--upon which he makes certain observations and explanations,
and suggestions for further investigations by philosophers.
With this letter there was enclosed a fifth contribution to the
Transactions. This article is entitled, "Meteorological Observations
made by William Dunbar, Esq., at the Forest, four miles east of the
Mississippi, in Latitude 31° 28´ North, and in Longitude 91° 30´ west
of Greenwich, for the year 1800; with remarks on the state of the
winds, weather, vegetation, etc., calculated to give some idea of the
climate of the country." In this article he says, "the frequent and
rapid changes in the state of the weather in this climate furnish an
excellent opportunity of verifying the vulgar opinion of the moon's
pretended influence at her conjunctions, oppositions and quadratures;
but truth compels me to say (what probably may be said of many similar
persuasions) that after a continued and scrupulous attention to this
object, I have not discovered any such regularity of coincidences,
which might justify the reverence with which those traditional maxims
are at this day received." After discussing a method of manufacturing
ice by artificial means, he concludes this communication with the
following observations on the storms of the Gulf Coast region: "It
is evident that the circular course of the vortex followed that of
the sun's apparent diurnal motion.--It is possible that if similar
observations are made upon all hurricanes, tornadoes and whirlwinds
they will be found universally to consist of a vortex with a central
spot in a state of profound calm."
Dunbar's next letter that is preserved in the Jefferson Papers is
one to John Vaughan bearing the date of March 21, 1802. In this the
writer says that he envies Vaughan's "happiness at the discovery of
a complete skeleton of a mammoth." He makes some observations on the
species to which this mammoth belongs and refers to recent discoveries
of a similar nature in the interior of Asia and Borneo. He gives the
results of recent geological observations on the nature of the soil and
the stratification of the same as shown by the banks of the Mississippi
at Natchez; also a discussion of stones, rocks, ores, mineral waters,
petrifaction, etc. He requests Vaughan to inform Dr. Bartram that since
writing him last, he has made several new discoveries of a botanical
and zoological nature which he here describes.
This letter also shows that Dunbar was one of the first Mississippians
to resort to inoculation for protection against small-pox. He asked
Vaughan to send him some fresh vaccine virus and stated that six
children in his own family had never "had that disease, besides a
lengthy list of Black people, both young and old." Vaughan complied
with this request by sending the virus and asked Jefferson to do
likewise, stating that "the Vaccine inoculation gathers strength
hourly, _no_ respectable practitioner (of Philadelphia) opposes it."
January 15, 1803 Dunbar wrote to Jefferson: "Bad health which has
endured above twelve months has withheld much of my attention from
Philosophic objects, a favorable change having lately taken place, I
perceive with satisfaction that my mind and body are both recovering
their former tone and now again enjoy the pleasing prospect of
dedicating my leisure hours to my favorite amusements."
Dunbar's next contribution to the Transactions was entitled, "Abstract
of a communication from Mr. Martin Durale, relative to fossil
bones, etc., of the County of Opelousas, west of the Mississippi to
Mr. William Dunbar of the Natchez," etc. In this account Dunbar, in
referring to certain phenomena makes use of the following expression,
which has characterized the true philosophers of all ages, "I have
never observed them without endeavoring to ascertain the cause of them."
This communication was accompanied by "pretty full vocabularies of the
tongues of two Indian nations of that country," to which "was added
a sketch of the religion or superstition of these people." In this
connection, Dunbar says, "From several other quarters I have used some
efforts to draw similar information, but am hitherto disappointed."
He also makes mention of a letter which he had just received from Sir
Joseph Banks with an extract from the Transactions of the Royal Society.
January 28, 1804, Dunbar wrote to Jefferson transmitting his seventh
and eighth contributions to Volume Six of the Transactions, while an
extract from his letter was published as a ninth contribution. His
seventh article was entitled a "Description of the river Mississippi
and its Delta, with that of the adjacent parts of Louisiana." In this
he gives a table of the mean altitude of the waters of the Mississippi
at Natchez, from the lowest ebb to the highest elevation for the
first and fifteenth of each month in the year. It also contains a
good account of overflows and some philosophical reflections on the
velocity, banks, currents, deposits and depth of the river and the
effects of confining it to its channel. In speaking of the overflow
lands he says, "although no successful attempt is likely to be made in
our day, yet posterity will reclaim" them. He discusses the methods
used in Holland and in Egypt, and makes several speculations as to
the method that will probably be successful. This sketch, he says, in
conclusion, "is the result of occasional observation for a series of
years and of scattered information collected from various sources,
probably often uncertain, from a cause which is unfortunately, too
general; viz: the extreme inattention of persons, even of some
education to the most curious phenomena passing daily under their
review."
The eighth article was entitled: "Monthly and Annual Results of
Meteorological Observations" for the years 1801, 1802, 1803.
In an appendix to his seventh article, he discusses the writings of
certain Italian, French and German scientists, giving his reasons for
differing with them on certain philosophical questions. His discussion
is devoted largely to a consideration of certain laws of hydrostatics.
His "Observations on the eclipse of the sun, June 16, 1806" made in his
private observatory on Union Hill, constitutes his tenth contribution
to the publication mentioned above. This article gives a vivid account
of the excited state of mind with which an astronomer awaits the time
when nature affords favorable opportunities for investigating her
mysteries. It also shows that this frontier scientist of Mississippi
enjoyed in thought, as he could not by personal association, the
companionship of the great thinkers of the world. These are his words:
"The moment of the expected impression approached and reflecting
that this eclipse was to be seen all over Europe and North America
which renders it a very important phenomenon for settling comparative
longitudes, I conceived that all the zealous astronomers of both worlds
were then looking with me at the great luminary and centre of our
system. I kept my eye riveted upon that point of the disk where the
eclipse was to commence, with an anxiety known only to astronomers;
with the chronometer watch at my ear, I attended to the most doubtful
appearances which my perturbation perhaps presented to the eye, and
upon every alarm, began to count the beats of the watch (five in two
seconds) in order that I might not lose the very first instant of the
impression, and I am confident that not one quarter of a second was
lost."
The last letter that has been preserved from the interesting
correspondence between Dunbar and Jefferson, bears the date of
Dec. 17, 1805. With it was enclosed Dunbar's "Method of finding the
Longitude by a single observer without any knowledge of the precise
time," a problem that had been solved by him at Jefferson's request.
This formed an eleventh contribution to the publication referred to
above.
There is no reason for doubting that this correspondence was continued
throughout the remaining four years of Dunbar's life, though the
letters have not been found by the writer.
Dunbar's last contribution to the Transactions was entitled:
"Observations on the Comet of 1807-'8." It was read before the Society
Nov. 18, 1808. In this article appears at least one entry which
indicated that the scientific services of its author were drawing
to a close. "Indisposition," says he at one point in the narrative,
"prevented observation for some time past." A few months from this date
the scientific investigation of this remarkable man were brought to a
close.
Writers have frequently noted the fact that many great men have lived
in advance of their times. To substantiate this assertion they cite us
to the careers of Copernicus, Galileo, Newton, and a host of others.
That Dunbar is entitled to the same distinction might be amply proved
by a study of his life.
The most conclusive evidence of this fact is furnished by his idea of
the relation the government should sustain to scientific explorations.
In a letter to John Vaughan, bearing the date of March 21, 1802, he
writes as follows:
"There is no example of any encouragement being held out
by [our] Government; no spirit of inquiry set on foot at
the public expense. What is the reason, we have no State
observatory to which individuals might send their contributions
& from which they might receive astronomical intelligence....
No naturalist travels at the public expense to explore our
immense country & make us acquainted with the infinite
resources it Contains upon its surface, in its waters & within
its bowels, from whence great national advantages would result;
the public & individuals would be instructed where to direct
their researches after such objects as might become subjects
of curiosity, Public the exercise of genius & agrandizem't
of fortune; but it would seem that the speculations ... of
our politicians are confined within the narrow circle of the
Customs & Excise, while literature of our present illustrious
President will correct & enlarge the views of our public men,
& that under his auspices & protection, Arts, Science, &
Literature may take a flight, which will at length carry them
beyond those European brethren, as wel[l] to[o] as above them
in the enjoyment of national liberty."
In transmitting this letter to Jefferson, Vaughan says of Dunbar, "he
is like yourself a warm friend to the encouragement of Science and
letters, it would be fortunate for the country, if these ideas became
more prevalent."
Remarkable to relate, two years had not elapsed after Dunbar had
written this despondent letter before he saw evidences of a partial
fulfillment of his desire and three months later still, he was
appointed a member of one of the first expeditions sent out for
scientific purposes at the expense of the government of the United
States. In a letter to President Jefferson, written May 13, 1804,
Dunbar says: "The surveying and exploring expeditions to be undertaken
at public expense must be most gratifying to all lovers of science
and natural research.... It will give me the highest satisfaction to
contribute everything in my power to promote the proposed expedition on
the Red and Arcansa Rivers."
Owing to the dissentions among the Osage Indians, the main part of
this expedition was postponed, however, until the spring of 1805.
In a letter bearing the date of July 14, 1804, Jefferson wrote to
Dunbar:--"It is very desirable that you make use of any part of the men
or matters provided for the expedition and go to what distance, and
in what direction you please, return when you please, but in time to
report to us the result of your researches, which report will probably
induce Congress to enlarge the appropriation."[58]
August 18, 1804 he wrote Jefferson that, "in consequence of the
permission you are pleased to grant, I have determined to make an
excursion up the Washita river and to the hot springs." Two months
later, he wrote that he had about completed the necessary preparations
for the expedition and that he would carry "several instruments [of his
own] in addition to those provided for the party" by the government.
Three weeks after writing the above letter, he again wrote to the
President from the Post of Washita giving him the latitude of the most
important points on the river.
After his return to Natchez, he wrote Jefferson the first scientific
account of the water at Hot Springs. Subsequent analyses of this water
have shown some inaccuracies in this account, but it must be remembered
that Dunbar was only a pioneer in this important field. His account
reads as follows:
"I have examined the water at 130° Fahrenheit under a powerful
microscope and found vegetable and animal life, the former
a species of moss, the latter a testaceous bivalve of the
size of the minutest grain of sand. I do not despair of being
able to reanimate these as soon as I can procure a little
leisure....[59] From our analysis of the water ... it appears
to contain lime with a minute portion of iron dissolved by a
small excess of Carbonic acid. This is ... visible upon the
first view of the Springs; an immense body of calcareous matter
is accumulated upon the side of the hill, by perpetual deposits
from the hot waters, and the bed of the run is coloured
red oxide of iron or rather Carbonated iron. Every little
spring which rises up in a favorable situation forms its own
calcareous cup considerably elevated in form of a crater."
The following year (1805) Dunbar was given the general supervision
of the Red River Expedition. May 24 of that year Mr. Dearborn, the
Secretary of War, wrote requesting him to make all arrangements for
this expedition, limiting the expenses to $5,000. In a letter bearing
the date of March 30, 1807, Mr.
Dearborn expressed his appreciation of Mr. Dunbar's services in the
following words:--"The frequent drafts on account of the United
States upon your time and patience demand an apology, while your
disinterestedness and highly useful services entitle you to the most
grateful acknowledgements."
Dunbar's idea of the relation the government should sustain to
scientific research is still further set forth in his last letter that
has been preserved in the Jefferson manuscripts. From this letter,
which bears the date of December 17, 1805, the following extract is
taken:
"I have just received from London a six feet Gregorian
reflecting Telescope with six magnifying powers from 110 to
550 times; hitherto from a liberal construction of the act
of Congress, by the Collectors of the Mississippi Territory
residing at Fort Adams, I have been in the habit of receiving
books and instruments free of duty, but Mr. Browne at New
Orleans is so rigidly faithful as a public servant that he
admits of no exemptions neither in favor of the Mississippi
Society, for which I have lately imported a chest of books;
nor in favor of this valuable instrument, the cost of which
in London was about 150 guineas, [about $750]. I suppose Mr.
Browne is quite correct as to the letter of the law.... I have
just sent off an order for Mr. Briggs, Mr. Dinsmore and myself,
for astronomical instruments & chronometers to the amount of
300 guineas [about $1,500], all of which as well as that just
received, will in some shape be applied to public use and
benefit & might therefore be entitled to a claim upon public
indulgence."[60]