405
Ihe science of horology is illustrated on the great as well as on the small scale in the large clocks and thechronometers exhibited in this Class. The large electric clock, the hands of which are seen projectingjh ® the south entrance of the Transept, is an interesting example of the application of the force of electro-t^ftism to move mechanical arrangement for the measurement of time. A small galvanic battery keepsjj ls targe instrument, and several other clocks in the Building, in regular movement. The ribs of the Transepts v ® oeen made to represent the dial, and show the hours from 6 a.m. to 6 p.m. Other electric clocks on ate . ar scale are shown, and exhibit various ingenious arrangements intended to effect the same end. Self-I>Ln^ er ^ n ?’ astronomical, and other clocks are likewise exhibited. In some of the large clocks for churches andhe buildings, one of which is in the Nave, and others are at the termination of the Galleries, new principlessuspension and compensation of the pendulum and of escapement are introduced. Much ingenuity hasto en ,. en expended upon clocks with a view of communicating to them the power of indicating, in additionth ,nary time, that of different places, and of different periodical occurrences, as the rise and fall of the tide,e day of the month, &c. Several of these clocks are shown, and particularly one which occupied its patient£ ns tfuctor thirty-four years in its manufacture. The watches and chronometers exhibited have also theirj. °uliar claims to attention. The escapements of some of the latter are in part neiv, and appear to promiseiii , 0Ura ble results. Several different specimens of watches, adapted for different markets, afford a curious^••Ustration of the variation of natural tastes—the variety of methods in which compensation for the changesEV* ' n 8 from variations of temperature is obtained both in chronometers and in astronomical and other clocks.C 1 tre mely small watches, as specimens of minute workmanship, are exhibited. The parts of watches andTl are likewise included in this Class.
RouT 6 Philosophical instruments exhibited comprise a large number connected with the display of the phe-a nd Da - an< ^ • the aneroid barometer, in which the mercurial column is dispensed with,
v . Va rions forms of the ordinary barometer are among them. Electric communications are now effected by ais i v apparatus of greater or less facility of application. Printing electric telegraphs, in which a messagenee n Cor< t e d by this agency, upon a chemically-prepared paper, appear in various forms with the ordinary■tyill 1 telegraph. The methods of electric insulation for telegraph uses are also exhibited. Among theseQ 0 . e regarded with interest the wires adapted for submarine communication between this country and thej, ®ent. The magnetic and electric machines, with electro-magnets of great power, are also interesting,gn ritls b manufacturers have for some time been making great efforts with a view of producing good opticalan d a skilful method of working it into the forms desired for optical purposes. These efforts have beenf 0re ; l ®kly successful that the glass produced in England is not unfrequently exported and again re-imported asgl a glass at a much higher price. The production of lenses has also greatly improved; and achromatictei es cons iderable size, as well as of a smaller kind, are made with success in this country. Microscopes,c k a ract ,eS ’ an< ^ ™ nor philosophical instruments, are now of excellent quality and highly-wrought
sp^^lography is included in this Class, both on plates of silver and glass, and on paper. The most beautifula hd <? ens °f sun-drawn pictures are exhibited. Daguerreotypes of every kind, plain and coloured, “ enamelled,”1’hg i cra yon,”—improvements of recent introduction, and applied to a variety of purposes,.—are found here.a re i ar § es t daguerreotype probably yet produced, a group of sculpture, is placed in this Class. The Talbotypes due i ° Ver y beautiful, and present a charming evidence of the fidelity and artistic effects capable of being pro-Phot ^ the P enc H °f Nature. Photographic apparatus of various kinds, together with the results of curiousate i° ra Phic experiments, illustrative of the distinct existence of luminous and actinic rays in the solar beam,a so represented.
the ®= rea, l variety of miscellaneous philosophical apparatus, for popular illustration, and for the purposes ofs ev ex P er rmentalist, is also displayed, and must attract notice. The musical instruments exhibited, includeEnf ra Powerful organs. That over the West Entrance possesses 80 stops. The organ over the Easternex hibits a new and pleasing arrangement of pipes, and possesses a powerful set of stops. The organPo\v f South Transept Entrance is devoid of a case, and exhibits the internal mechanism; it possesses ain a Ml u reed stop, and other stops. Pianos, harps, seraphines, of new modes of construction, and decoratedv alu e eniar ^ a bl e manner, are likewise found here. The instruments of the surgeon have a purely professionalft ’ he sou gbt by those interested in that pursuit,
fusion+ n ° *his Class as representing the culminating point of mechanical skill, it forms an appropriate con-quigjtg . those devoted to machinery generally. Delicacy and precision of workmanship are absolutely re-gent, the industry occupied in producing philosophical apparatus. It will be found, on inspection, that thecessf ul . this country, so remarkably developed in mechanics applied to commercial purposes, is not less suc-tu its application to the higher pursuits of experimental and practical philosophy.—R. E.