1851 Great Exhibition: Official Catalogue: Class X.: John J. Griffin and Co
457. GRIFFIN, JOHN J., and Co., 53 Baker Street — Manufacturers.
Graduated glass instruments for chemical testing in the arts; applicable to the examination of soda, potash, ammonia, the mineral acids, vinegar, bleaching powder, limestones, solutions of iron, silver, and other metals, salt-springs, white lead, and other chemical products; graduated measures for liquids, showing the usual divisions of the imperial gallon; and for gases.
Set of decimal weights and measures, founded on the imperial gallon and the avoirdupois pound, with explanatory tables.
Set of hydrometers, with Twaddell's scale of improved oval form.
Stokes' hydrometer for determining the strength of spirits of wine at any temperature, according to the degrees of Sikes', by means of one glass spindle, having two scales without weights, but with a thermometer.
Ammoniameter, or hydrometer for liquid ammonia. A glass spindle with a scale of 1000; every degree shows one test-atom or 212.5 grains of dry ammonia in a gallon of solution.
Small chemical apparatus, in a portable cabinet, adapted for analytical researches by naval and military officers, colonial engineers, etc.
Cabinet apparatus for use in colonial sugar-works, in determining the density of cane-juice, and the exact amount of lime required for properly clarifying the juice. Invented by Dr. Shier.
Apparatus for the chemical analysis of urine. Portable collection of chemical apparatus for elementary experiments.
Set of apparatus for testing the hardness of waters invented by Professor Clark.
[Clark's test for the hardness of water consists in adding a standard solution of soap to water until it produces a lather, the quantity used indicating the degree of hardness. Most waters contain lime in the state of carbonate, with some sulphate of lime, and chloride of sodium. The waters supplied to London give these substances in the following proportions, according to the analyses of Mr. Richard Phillips:—
Carb. of lime. Brentford. 16.000; Barnes. 16.900; Chelsea.16.500.
Sulph. of lime, chi. of sodium. Brentford. 3.400; Barnes. 1.700; Chelsea. 2.900.
Dr. Clark has shown that a certain measure of his test, solution of soap, is required to combine with each grain of carbonate of lime, and that the whole of it which is present in the water must combine with the soap before a lather will form. The apparatus exhibited is for measuring the soap solution with great accuracy, and for adding it drop by drop to the water under examination. The Board of Health requires that every new source of water supply should be thus examined, and the number of degrees of hardness stated according to Dr. Clark's scale. Some chemists have lately pointed out sources of error in this process, but Dr. Clark states these may be avoided by care. R. H.]
Chemical thermometers for corrosive liquors. Set of blowpipe apparatus for the examination of minerals. Collection of small specimens of minerals, in a portable cabinet, adapted for travellers in the colonies.
Models of crystals executed in pottery.
Apparatus for teaching agricultural chemistry in parish schools.
Test-bottles' with indelible inscriptions, for chemical use.
Glass vessels for holding chemical liquors, made in Bohemia.
Books of test-papers. Circular filter-papers.
Frame with pegs for test-tubes.
Stoneware lamp-furnace for chemical operations.
Beale's furnace for executing combustions in organic analysis by gas.
Beale's gas furnace for heating crucibles.
Improved achromatic microscope and polariscope, for naturalists and physicians.
Ackland's improved combination of Smee's galvanic battery, in which the kind and amount of power can be readily modified.
Ackland's improved form of medico-galvanic machine, with single current, producing great power in a small compass.