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Transactions of the 
tions ; the spheres being larger in the alkaline solution. Both 
solutions were left in a temperature ranging between 50'^ and 60° 
for a week, and at the end of that time the whole deposit was 
found transformed into needles. 
A parallel series of observations was next made with albumen. 
12. To a clear filtered solution of urate of soda in boiling water, 
one-third bulk of egg albumen was added when the temperature 
had fallen to 120°. On complete cooling, tufts of the ordinary- 
form of needle were deposited. 
13. Slightly alkaline urate was digested in distilled water at 
100° Fahr., and one-third bulk of egg albumen added. No crystal- 
line or formed precipitate, but formless tracts of molecular matter. 
14. Alkaline urate boiled in distilled water and filtered. Half 
bulk of egg albumen added to hot solution and the coagulated 
mixture cooled. Needles both in fluid and coagulum, with much 
molecular matter in coagulum. 
15. The mixture in 14 was now boiled for some time, in order 
that the coagulum might be fully saturated with the urate solution. 
On cooling, the flakes of albumen were found to have absorbed most 
of the urate. They contained large brown tracts of molecular 
matter, with faint indications of the presence of very small delicate 
needles. The solution contained no needles. 
16. The mixture was again heated, and a small excess of acetic 
acid added. Now there occurred granular deposit in the albumen, 
and a free formation of small thick rhombohedra on the surface 
of the flakes. On again heating and adding more acetic acid, rhom- 
bohedra and bright spheroids were formed. 
The influence of chlorides was now examined. Dr. Bence Jones 
in the year 1844 showed that the presence of chloride of sodium in 
solution with urate of ammonia prevented the formation of crystals 
and determined the occurrence of the molecular urate; and that 
the solubility of urate of ammonia was doubled by the presence of 
chloride of sodium. 
17. To a solution of urate with free uric acid as in 10, a strong, 
nearly saturated solution of chloride of sodium was added in equal 
bulk. On cooling, the liquid was found almost filled with a gela- 
tinous precipitate, which did not subside. It had just the appear- 
ance of freshly precipitated gelatinous silica. Under the micro- 
scope the gelatinous matter was found in well-defined masses, 
quite distinct from the liquid ; it had a mottling of bright points 
and obscurely indicated acicular crystals, which were often gathered 
into rounded groups. The crystals were irregularly interlaced, and 
gave rise to an appearance of polygonal cellular structure. Im- 
bedded in the gelatinous matter were numerous lengthened navi- 
cellse, and chisel-ended three-sided prisms. See Fig. 7. 
18. A similar experiment to 17 was made, with the substitution 
