WHITEHURST. 
thus compassed, he shortly after bid the 
artist farewell, and returned to his father in 
England. 
About two or three years after his return 
from Ireland, he left Congleton and entered 
into business for himself at Derby, where 
he soon got into great employment, and 
distinguished himself very much by several 
ingenious pieces of mechanism, both in his 
own regular line of business, and in various 
other respects, as in the construction of 
curious thermometers, barometers, and 
other philosophical instruments, as well as 
in ingenious contrivances for water-works, 
and the erection of various larger machines : 
being consulted in almost all the under- 
takings in Derbyshire, and in the neighbour- 
ing counties, where the aid of superior skill, 
in mechanics, pneumatics, and hydraulics, 
was requisite. 
In this manner his time was fully and use- 
fully employed in the country, till, in 1775, 
when the act being passed for the better re- 
gulation of the gold coin, he was appointed 
stamper Of the money-weights; an ofEce 
conferred upon him, altogether unexpect- 
edly, and without solicitation. Upon this 
occasion he removed to London, where Itg 
spent the remainder of his days, in the con- 
stant habits of cultivating some useful parts 
of philosophy and mechanism. 
In 1778, Mr. Whitehurst published his 
Inquiry into the Original State and Forma- 
tion of the Earth; of which a second edition 
appeared in 1786, considerably enlarged 
and improved ; and a third in 1792. This 
was the labour of many years; and the nu- 
merous investigations necessary to its com- 
pletion, were in themselves also of so unto- 
ward a nature as at times, though he was 
naturally of a strong constitution, not a 
little to prejudice his health. When he first 
entered upon this species of research, it was 
not altogether with a view to investigate 
the formation of the earth, but in part to 
obtain such a competent knowledge of sub- 
terraneous geography as might become sub- 
servient to the purposes of human life, by 
leading mankind to the discovery of many 
valuable substances which lie concealed in 
the lower regions of the earth. 
May the 13th, 1779, he was elected and 
admitted a Fellow of the Royal Society. 
Before he was admitted a member, three 
several papers of his had been inserted in 
the Philosophical Transactions, viz. Ther- 
mometrical Observations at Derby, in vol. 
67 ; An Account of a Machine for raising 
Water, at Oulton, in Cheshire, in vol. 65 ; 
and Experiments on Ignited Substances, 
vol. 66 : which three papers were printed 
afterwards in the . collection of his works 
in 1792. 
In 1783, he made a second visit to Ire- 
land, with_ a view to examine the Giant’s 
Causeway, and other northern parts of that 
island, which he found to be chiefly com- 
posed of volcanic matter : an account and 
representation of which are inserted in the 
latter editions of his Inquiry. During this 
excursion he erected an engine for raising 
water from a well, to the summit of a hill, 
in a bleaching-ground at Tullidoi, in the 
county of Tyrone, which is worked by a 
current of water. 
In 1787, he published An Attempt to- 
ward obtaining Invariable Measures of 
Length, Capacity, and Weight, from the 
Mensuration of Time. His plan is to ob- 
tain a measure of the greatest length that 
cbnveniency will permit, from two pendu- 
lums whose vibrations are in the ratio of 2 
to 1, and whose lengths ’ coincide nearly 
with the English standard in whole numbers. 
The numbers which he has chosen show 
much ingenuity. On a supposition that the 
length of a second’s pendulum, in the lati- 
tude of London, is 39J inches, the length of 
one vibrating 42 times in a minute, must be 
80 inches ; and of another vibrating 84 times 
in a minute, must be 20 inches ; and their 
difference 60 inches, or five feet, is his 
standard measure. By the experiments, 
however, the difference between the lengths 
of the two pendulum rods, was found to be 
only 59.892 inches, instead of 60, owing to 
the error in the assumed length of the 
second’s pendulum, 39t inches being greater 
than the truth, which ought to be 39 a very 
nearly. By this experiment, Mr. White- 
hurst obtained a fact, as accurately as may 
be in a thing of this nature, viz. the diffe- 
rence between the lengths of two pendulum 
rods whose vibrations are known : a datum 
from whence may be obtained, by calcula- 
tion, the true lengths of pendulums, the 
spaces through which heavy bodies fall in a 
given time, and many other particulars re- 
lating to the doctrine of gravitation, the 
figure of the earth, &c. 
Mr. Whitehurst had been at times sub- 
ject to slight attacks of the gout, and he 
had for several years felt himself gradually 
declining. By an attack of that disease in 
his stomach, after a struggle of two or three 
months, it put an end to his laborious and 
useful life, on the 18th of February, 1788, 
in the 75th year of ids age, at his'house in 
