1872.] The International Exhibition. 413 
mens of gunpowder (R.L.G., L.G., pebble, pellet, and prismatic) recently 
tried by the Committee on Explosives; also a crusher-gauge for dire@ly 
determining the pressure of fired gunpowder. Messrs. Bessemer have a very 
complete series of sectional models illustrating the Bessemer principle of 
constructing Continuous Low Pressure Ordnance. From Sir Joseph Whit- 
worth and Co. there are excellent models of a Six-pounder Breech-loading 
Rifled Gun and Carriage, made of Sir Joseph Whitworth’s patent compressed 
metal; and models of a breech-loading field-gun and a breech-loading naval 
gun and carriage. Major W. Palliser, C.B., shows a Service Muzzle-loading 
64-pounder Rifled Gun, converted on the Palliser principle from a smooth 
bore 32-pounder gun, and having fired 2300 rounds. These are in the 
West Arcade. Returning to the South Gallery we have, completing the list 
of furnaces and heating apparatus, the Newport Patent Puddling Furnace and 
Boiler invented by Jones, Howson, Gjers, and J. Head; also a seétional 
model of Whitwell’s Patent Hot-Blast Fire-brick Stove, ereéted at the 
moderate cost of £850 to £1000. Near at hand is a model of an admirable 
Boat Lowering Apparatus invented and exhibited by Mr.E. J. Hill. This 
apparatus appears to be extremely simple; by a peculiar form of eye it is con- 
trived that should either end of the boat alone touch the water, the eyes are not 
liberated ; should the boat touch the surface of the water in the complete plane, 
the eyes are immediately disengaged and the boat set free. The direct applica- 
tion of recently discovered scientific principles meets with but slight repre- 
sentation in the present Exhibition. Dr. Siemens, F.R.S., exhibits his Deep 
Sea Photometer, an apparatus for comparing the intensities of light at 
different depths of water. This photometer was used on board H.M.S. Shear- 
water, in August, 1871, in the Straits of Gibraltar. Dr. Siemens also contri- 
butes an Apparatus for Working Pneumatic Despatch Tubes on the continuous 
current system, as established for the transmission of postal telegrams 
between the West Strand and Central Telegraph Stations, together with an 
exhauster or steam-jet for drawing the air through the tubes. Colonel 
H. Stuart Wortley exhibits some results of his New Dry Photographic 
Process, for working, by the use of collodio-bromide of silver, without a silver 
bath. Passing from the gallery containing the preceding exhibits, the visitor 
interested in the useful application of science to every day purposes, will pause 
before the table at which an attendant of Messrs. D. Nicoll and Co. explains 
the use of a Fire-proof Starch. This starch renders fabrics uninflammable 
without affecting their colour, strength, or appearance, and requires only 
ordinary treatment by the laundress; it can be obtained in small quantities at 
a moderate price. 
Science, as represented in its own division, may be said to have now been 
exhausted by our imaginary visitor; but the ground upon which Science and 
Art marshal their combined forces is where the several kinds of musical 
instruments are exhibited. The instrument of general interest, the pianoforte, 
appears either in the gorgeous case-work of Messrs. Hopkinson and of 
Messrs. Erard, whose instruments are marvels of marqueterie work, or in the 
full-toned bijou pianofortes of the former firm, certainly the most powerful 
of the middle-class instruments, and in this respect not inferior to some of 
the grands exhibited. The Iron-Bijou-Grand Pianoforte, as well as the Full 
Concert-Grand contributed by this firm, are worthy of notice in a scientific 
point of view, from the substitution of iron for wood in those portions of 
the instrument subject to strain. When we consider that the strings of a 
seven-octave pianoforte tuned to concert-pitch exert a tension equal to nearly 
a half-score of tons, the employment of some material occupying less space 
and of more regular structure than wood is evidently desirable. 
The applications of eleétricity are yearly becoming more numerous, and 
since its first employment in organ construétion by Mr. Barker, of Paris, it has 
received considerable attention from Messrs. Bryceson Brothers and Co., 
who built their first electric organ for Her Majesty’s Opera in 1868. The 
organ exhibited in the present Exhibition consists of one manual and eight 
stops. A voltaic battery, electro-magnets, and attenuated air as a motive 
power, are the chief agents employed. Each key is connected to a separate 
