1070
navigation and natural magnets or lodestones were used
to demonstrate the power of magnetism.
Pneumatics, the study of air and gases, and especially
the creation of a vacuum led to the development of air
pumps from the late seventeenth century.
Hydrostatics. This was the name given to apparatus
used for demonstrating all effects involving water. This
ranged from model diving bells that made use of pres-
sure to move a model up and down a water-fi lled cyl-
inder, to the Tantalus cup demonstrating the siphon, to
elaborate fountains and the use of water under pressure.
Instruments such as the hydrometer were developed to
measure specifi c gravity.
Electricity was studied extensively during the eigh-
teenth and nineteenth centuries and machines were
developed to produce electricity and then to store it.
Static electricity was studied and machines produced in
the later eighteenth century culminating the Winshurst
machine that used two counter-rotating glass disks to
generate static electricity to produce an electric spark.
Many electric devices were used as forms of popular en-
tertainment. Geissler tubes were glass tubes containing
a high vacuum which contained gases that glowed when
electricity was passed through them. The discovery of
electric current lead to the development of measuring
instruments such as the electrometer and galvanometer
and storage methods such as the Leyden jar.
Heat—apparatus was developed to show that some
materials expand and contract under heat, that mirrors
could be used to focus heat and the nature of heat as an
energy form which lead to the development of Crooke’s
radiometer.
Sound demonstrations in the eighteenth century
were limited with the principal experiment showing
that a noise disappeared in a vacuum. In the nineteenth
century work into tuning forks and resonance lead to the
development of the telephone and phonograph.
Meteorological instruments. The refi nement of the
principal meteorological instruments occurred during
the eighteenth century with the thermometer to measure
temperature; the hygrometer to demonstrate humidity in
the air; and barometer to measure air pressure.
Light—which had most relevance to photography—
was studied through apparatus designed to demonstrate
and make use of scientifi c discoveries. Early studies
traced light through different media such as water, the
use of mirrors and light through lenses and prisms.
Microscopes and telescopes made use of the develop-
ment of advances in lens design and the understanding
of refraction and refl ection of light. Mirrors appeared
as Claude Lorraine glasses for drawing, and in differ-
ent forms to view anamorphic drawings. The camera
obscura made use of lenses, mirrors and the camera
lucida used a prism, to aid drawing. The zograscope,
stereoscope, magic lantern and kaleidoscope all derive
from optical study.
Allied to this was the study of the eye and how it
worked with the brain. The demonstration of persistence
of vision was shown through the thaumatrope, phena-
kistiscope, zoetrope and praxinoscope.
Other areas of optical study also developed instru-
ments such as the polariscope and polarimeter which
made use of the discovery of polarisation. The spectro-
scope allowed chemical composition to be determined
through the study of emitted light. According to Turner
the spectroscope ‘contributed more to modern science
than any other instrument’.
The development of instruments to study and dem-
onstrate scientifi c principals lead to a rapid increase in
scientifi c knowledge during the nineteenth century and
a growth of scientifi c instrument makers who produced
the standard demonstration instruments as well as their
own variants and entertainments based on scientifi c
principles. In 1701 there were 151 instrument maker’s
working in the British Isles which had increased to 837
by 1851. It was from the group of ‘optical and philo-
sophical instrument makers’ that the fi rst photographic
retailers and specialised photographic manufacturers
emerged in the early 1840s and 1850s.
Michael PritchardFurther Reading
Clifton, Gloria, Directory of British Scientifi c Instrument Makers
1550–1851, London: Zwemmer, 1995.
Hackmann, W.D., “The Nineteenth Century Trade in Natural
Philosophy Instruments in Britain.” In Nineteenth Century
Scientifi c Instruments and their Makers, edited by P.R. de
Clerq, Amsterdam: Editions Rodopi, 1985.
Holbrook, Mary, Science Preserved. A Directory of Scientifi c
InstrumentsCcollections in the United Kingdom and Eire,
London: HMSO, 1992.
Turner, Gerard L’E, Nineteenth Century Scientifi c Instruments,
London, 1983.
——, Scientifi c Instruments 1500–1900. An Introduction, Lon-
don: University of Berkeley, 1998.PHILOSOPHICAL MAGAZINE
Using the relatively new printing technology of stereo-
typing, the Philosophical Magazine was launched in
1798 by Alexander Tilloch (1759–1825):
the grand Object of it is to diffuse Philosophical Knowl-
edge among every Class of Society, and to give the Public
as early an Account as possible of every thing new or
curious in the scientifi c World, both at Home and on the
Continent. (‘Preface,’ Philosophical Magazine, 1, 1798)
Initially, the journal was in competition with an-
other recently-founded periodical, William Nicholson’s
Journal of Natural Philosophy, Chemistry and the