SIM 
templated with great pleasure the rugged 
top of Chiggre, to which we were fast ap- 
proaching, and where we were to solace 
ourselves with plenty of good water, Idris, 
our guide, cried out, with a loud voice, fall 
upon your faces, for here is the simoom. I 
saw from the south-east a haze coming, in 
colour like the purple part of the rainbow, 
but not so compressed or thick. It did not 
occupy twenty yards in breadth, and was 
about twelve feet high from the ground. 
It was a kind of blush upon the air, and it 
moved very rapidly ; for I scarce could turn 
to fall upon the ground with my head to the 
northward, when I felt the heat of its cur- 
rent plainly upon my face. We all lay flat 
on the ground as if dead, till Idris told us it 
was blown over. The meteor or purple 
haze which I saw was indeed passed; but 
the light air that still blew was of heat to 
threaten suffocation. For my part, I found 
distinctly in my breast that I had imbibed a 
part of it, nor was I free from an asthmatic 
sensation till I had been some months in 
Italy, at the baths of Poretta, near two 
years afterwards.” Though the severity of 
this blast seems to have passed over them 
almost instantaneously, it continued to blow 
so as to exhaust them till twenty minutes be- 
fore five in the afternoon, lasting through all 
its stages very nearly six hours, and leaving 
them in a state of the utmost despondency. 
SIMPLE, something not mixed or com- 
pounded, in which sense it stands opposed 
to comppund. 
' Simple, in pharmacy, a general name 
given to all herbs or plants, us having each 
its particular virtue, whereby it becomes a 
simple remedy. 
Simple Contract, in law, debts by simple 
contract, are such where the contract upon 
which the obligation arises is neither ascer- 
tained by matter of record, nor yet by spe- 
cial deed or instrument, but by mere oral 
evidence, or by notes unsealed; wliereas 
debts by speciality are such whereby the 
contract is ascertained by deed or instru- 
ment, under seal. Simple contract debts 
are to be paid by executors after debts by 
speciality. 
SIMPSON (Thomas), in biography, 
professor of mathematics at the Royal Aca- 
demy at Woolwich, fellow of the Royal 
Society, and member of the Royal Acade- 
mv, at Stockholm, was born at Market 
Bosworth, in Liecestershire, in 1710. His 
father, a stuff-weaver, taught him only to 
read English, and brought him up to his 
own business; but meeting with ascienti- 
SIM / 
fic pedlar, who also practised fortune- 
telling, young Simpson, by his assistance 
and advice, left off weaving, and professed 
astrologyl As he improved in knowledge, 
however, he grew disgusted with his pre- 
tended art, and, renouncing it, was driven 
to such difficulties for the subsistence of his 
family, that he came up to London, where 
he worked as a weaver, and taught mathe- 
matics at his spare hours. As his scholars 
increased, his abilities became better known, 
and he published his Treatise on Fluxions, 
by subscription, in 1737 ; in 1740 he pub- 
lished his Treatise on the Nature and Laws 
of Chance ; and Essay in Speculative and 
Mixed Mathematics. After these appeared 
his Doctrine of Annuities and Reversions ; 
Mathematical Dissertations ; Treatise on 
Algebra ; Elements of Geometry ; Trigono- 
metry, Plane, and Spherical ; Select Exer- 
cise ; and his Doctrine and Application of 
Fluxions, which he professes to be rather a 
new work, than a second edition of his for- 
mer publication on fluxions. In 1743, he 
obtained the mathematical professorship at 
Woolwich Academy; and soon after was 
chosen a member of the Royal Society, 
when the president and council, in consi- 
deration of his moderate circumstances, 
were pleased to excuse his admission-fees, 
and his giving bonds for the settled future 
payments. At the academy he exerted all 
his abilities in instructing the pupils, who 
were the immediate objects of his duty, 
as well as others whom the superior offi- 
cers of the ordnance permitted to be board- 
ed and lodged in his house. In his manner 
of teaching he had a peculiar and happy 
address, a certain dignity and perspicuity, 
tempered with such a degree of mildness, 
as engaged the attention, esteem, and friend- 
ship, of his scholars. He therefore Required 
great applause from his superiors in the 
discharge of his duty. 
Mr. Simpson’s Miscellaneous Tracts, 
printed in 4to., 1757, were his last legacy 
to the public : a most valuable bequest, 
whether we consider the dignitj' and im- 
portance of the subjects, or his sublime 
and accurate manner of treating them. 
The first of these papers is concerned in 
determining the Precession of the Equinox, 
and the different Motions of the Earth’s 
Axis, arising from the Attraction of the 
Sun and Moon. It was drawn up about 
the year 1752, in consequence of another 
on the same subject, by M. de Sylvabelle, 
a French gentleman. Though this gentle- 
man had gone through one part of the sub- 
