Scientific Intelligence, Sfc. 151 



suiting from the concentration of the coloured |)articles, nor an 

 agregation around the crystal, while it increased with great rapidity ; 

 yet even by sprinkling a fine powder over the liquid which crystal- 

 lized, no currents could be detected. Hence, crystallization isanalo- 

 gous to the phenomena which it is generally supposed take place 

 when masses agregate in space. A nebulous appearance first occurs, 

 the matter of which gradually condenses in the centre, then a kernel 

 is formed with an areola, and lastly a properly formed world is com- 

 pleted. 



Ehrenberg has carefully studied some drops of a solution of com- 

 mon salt, and has observed that hexagonal tables are formed at the 

 limit of evaporation often very regular but frequently deposited one 

 upon the other. In the middle of these very delicate hexagonal tables 

 a point was suddenly formed which attracted to it the mass of tables. 

 Immediately the observer noticed there a small tube increasing with 

 immense rapidity and enlarging as the tables diminished. The water 

 of the Baltic and N. Sea are particularly fitted for these observa- 

 tions. Conceiving that the phenomena might be owing to the pre- 

 sence of two different salts, he made an experiment upon common 

 salt, chemically pure and dissolved in distilled water. In this case 

 he observed the same, only not so frequently ; the cubes being gene- 

 rally formed immediately. Mitscherlich has shown that common 

 salt forms hexagonal plates at very low temperatures. But in the 

 present case the temperature was that of the atmosphere. Did the 

 cold produced by the evaporation influence it? — Poggendorff's 

 Ann, No. x., 1835. 



III. — Uric Acid Calculi in the Biliary Canals. 

 Dr. Aube in dissecting the Lucanus Capreolus found two small 

 gray rough calculi with a crystalline appearance, which were found 

 by Audouin to consist of uric acid. These vessels, to which the 

 name of biliary has been given by modern anatomists, are small in- 

 sulated canals, commonly in the Caecum, and open behind the 

 stomach either by a single mouth or by two. Sometimes one of 

 these extremities opens near the anus. Meckel considered that 

 they secreted a liquid similar to the urine, while Gaede conceived 

 that they were absorbents. The circumstance of uric acid calculi 

 being found in them, however, supports the opinion of Meckel. — 

 Bibiiot. Unicers., April, 1836. 



IV. — Effect of the price of Corn upon the Population. 



M. DuPiN has examined this question, by taking the average from the 

 year 1817 to 183*2. The mean annual price of corn during that period 

 has varied from 36 francs 16 cents to 154 fr. 49 c. per hectrolitre. 

 Taking the average of deaths for the 6 years when corn was dear 

 and 6 when it was cheap, we have 



Mean Price. Annual Deaths. 



25 fr. -06 c. h 25023 



16 -44 " 24950 



