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Hartford county, Connecticut; 11 miles north-west of 
Hartford. Population 1966. 
SIMSIA [so called by Mr. Brown, in honour of Dr. John 
Sims], in Botany, a genus of the class tetrandria, order 
monogynia, natural order of proteaceee (Juss.) —Gene¬ 
ric Character. Calyx none, unless the corolla be taken 
for such. Corolla : petals four, inferior, linear-oblong, equal, 
deciduous; reflexed at the extremity. Nectary none. Stamina: 
filaments four, awl-shaped, prominent, inserted into the disk 
of each petal; anthers roundish, cohering, so that the ad¬ 
joining lobes of each make one common cell, at length sepa¬ 
rating. Pistil: germen superior, obovate; style cylindrical; 
stigma dilated, concave. Pericarp: nut inversely conical, of 
one cell, naked.— Essential_ Character. Petals four, equal, 
reflexed, without nectariferous glands. Stamens prominent; 
anthers cohering; their adjoining lobes making a common 
cell. Stigma dilated, concave. Nut inversely conical. 
1. Simsia tenuifolia, or slender leaved Simsia.—Heads 
naked, mostly solitary on each branch of the panicle, accom¬ 
panied by small partial bracteas.—Found in New Holland. 
2. Simsia anethifolia, or fennel-leaved Simsia.—Heads 
numerous in each panicle, and about as long as its partial 
branches, accompanied by imbricated involucral leaves.— 
Gathered on the sandy sea-shores of the same country. 
S1MSON (Robert), was born in the year 1687, of 
a very respectable family, in the county of Lanark. He 
was educated in the university of Glasgow, where he 
made great progress in his studies, and acquired in every 
branch of science a large stock of information, which, if it 
had never been greatly augmented afterwards, would have 
done great credit to any professional man. He became, at 
an early period, an adept in what was denominated the phi ■ 
losophy and theology of the schools, and was able to supply 
■with great credit the place of a sick relation in the class of 
oriental languages. While he was pursuing a course of 
theology, as preparatory to his entering into orders, mathe¬ 
matics took hold of his fancy, and he would, in after-life, say 
that be amused himself in his favourite pursuit, while he was 
actually preparing his exercises for the divinity hall. When 
fatigued with speculations, in which he could not meet with 
certainty to reward his labours, he relieved his mind, ardent 
in the pursuit of truth, by turning to mathematics, with which 
he never failed to meet with what would satisfy and refresh 
him. For a long time he restricted himself to a very mode¬ 
rate use of the cordial, fearing that he should soon exhaust 
the stock which so limited and abstract a science was capable 
of yielding; at length, however, his fears were dissipated on 
this head, for he found that the more he learned, and the 
farther he advanced, the more there was to learn, and a still 
wider field opened to his view. He accordingly determined 
to make the mathematics the profession of his life, and gave 
himself up to the study without reserve. It is said, that his 
original incitement to this science as a treat, as something to 
please and refresh the mind in the midst of severer tasks, gave 
a particular turn to his mathematical pursuits, from which he 
could never deviate. He devoted himself chiefly to the an¬ 
cient method of pure geometry, and felt a decided dislike to 
the Cartesian method of substituting symbols for the opera¬ 
tions of the mind, and still less was he willing to admit sym¬ 
bols for the objects of discussion, for lines, surfaces, solids, and 
their affections. He was rather disposed in the solution of 
an algebraical problem, where quantity alone is to be consi¬ 
dered, to substitute figure and its affections for the algebraical 
symbols, and to convert the algebraic formula into an analo¬ 
gous geometrical theorem. In so little respect did he come at 
last to consider algebraic analysis, as to denominate it a mere 
mechanical knack, in which he would say we proceed with¬ 
out ideas of any kind, and obtain-a result without meaning, 
and therefore without any conviction of its truth. 
About the age of twenty-five Dr. Simson was chosen pro¬ 
fessor of mathematics in the university of Glasgow. He im¬ 
mediately went to London, and there formed an acquaintance 
with the most eminent men who at that time flourished in the 
metropolis. Among these was the celebrated Halley, of 
whom he always spoke with the most marked respect, saying 
SON. 
that he had more acute penetration, and the most just taste in 
that science, of any man he had ever known. Dr. Simson 
also admired the masterly steps which Sir Isaac Newton was 
accustomed to take in his investigations, and his manner of 
substituting geometrical figures for the quantities which are 
observed in the phenomena of nature. He was accustomed 
to say, that the 39th proposition of the first book of the 
Principia, was the most important proposition that had ever 
been exhibited to the physico-mathematical philosopher, and 
he used to illustrate to the higher classes of his pupils, the 
superiority of the geometrical over the algebraic analysis, by 
comparing the solution given by Newton, of the inverse 
problem of centripetal forces, in the 42d proposition of that 
book, with the one given by John Beruouilli, in the memoirs 
of the Academy of Sciences at Paris, for the year 1713. 
Returning to his mathematical chair, Dr. Simson discharged 
the duties of a professor, for more than half a century, with 
great honour to the university and to himself. It is scarcely 
necessary to add, that in his lectures he always made use of 
the geometry of Euclid, in preference to those works which 
he thought leaned too much to analysis. His method of 
teaching was simple and perspicuous, his elocution clear, and 
his manner easy and impressive. He uniformly engaged the 
respect and affection of his pupils. 
It was owing to the advice of Dr. Halley that our author 
so early directed his efforts to the restoration of the ancient 
geometers. He had recommended this to him as the most 
certain means of acquiring a high reputation, as well as to 
improve his taste, and he presented him with a copy of 
Pappus’s Mathematical Collections, enriched with his own 
notes. The perspicuity of the ancient geometrical analysis, 
and the elegance of the solutions which it affords, induced 
him to engage in an arduous attempt, which was nothing less 
than the entire recovery of this method. His first task was 
the restoration of Euclid’s Porisms, from the scanty and 
mutilated account of that work in a single passage of Pappus. 
He, however, succeeded, and so early as 1718, seems to have 
been in possession of this method of investigation, which 
was considered by the eminent geometers of antiquity as 
their surest guide through the intricate labyrinths of the 
higher geometry. In 1723, Dr. Simson gave a specimen of 
this discovery in the Philosophical Transactions; and after 
that period he continued with unremitting assiduity to restore 
those choice porisms which Euclid had collected, as of the 
most general use in the solution of difficult problems. Having 
obtained the object of which he was in pursuit, he turned 
his thoughts to other works of the ancient geometers, and 
the Porisms of Euclid had now only an occasional share 
of his attention. The Loci Plani of Apollonius were the 
next task in which he engaged, and which he completed 
in the year 1738 ; but after it was printed he was far from 
being satisfied that he had given the identical propositions 
of that ancient geometer; he withheld the impression several 
years, and it was with extreme reluctance that he yielded 
to the entreaties of his mathematical friends in publishing 
the works in 1746, with some emendations in those cases 
in which he thought he had deviated the most from the 
author. Anxious for his own reputation, and fearing that 
he had not done justice to Apollonius, he soon recalled all 
the copies that were in the hands of the booksellers, and the 
impression lay by him several years. He afterwards revised 
and corrected the works, and even then did not, without 
some degree of hesitation, allow it to come into the world 
as the restoration of Apollonius. The work was, however, 
received by the public with great approbation ; the author’s 
name became better known; and he was now considered as 
among the very first and most elegant geometers of the age. 
He had, previously to this, published his Conic Sections, a 
treatise of uncommon merit, whether considered as a com¬ 
plete restitution of the celebrated work of Apollonius Pergaeus, 
or as an excellent system of this useful branch of mathe¬ 
matics. This work was intended as an introduction, or pre¬ 
paratory piece, to the study of Apollonius, and he has ac¬ 
cordingly accommodated it to this purpose. The intimate 
acquaintance which Dr. Simson had now acquired with all 
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