CONTENTS. V 



Page. 



11,12. Daily magnetic variation — Economical process for im- 

 itating silver paper, - - - - 189 



13, 14, 15. Pressure of sand — Cement from iron filings — Con- 

 centration of sound, _ _ _ . 190 



16, 17. Dangerous plant among water-cresses — Thunder storms 



in France, - - - - - -191 



STATISTICS. 



1. Mortality of infants, - - - - - 192 



2, 3. Phthisis pulmonalis in Paris — Establishment of a model 



farm in Greece, - - - - - 193 



4, Science in Madrid, - - - - - 194 



5, 6. Hygiene — English Universities, - - - 195 



ADDITIONAL EDITORIAL SELECTIONS. 



1. Dr. Mitchell's method of working caoutchouc, - - 195 



2. Strength of wine and other bottles, - - - 196 



3. Magnesium — Metal of magnesia, - - - 197 



4. 5. Decrepitating common salt — Manufacture of bicarbonate 



of soda, ..-_._ 198 



6, 7. Russia diamond mines— Premature Explosions, - 199 



ADDITIONAL EXTRACTS, BY PROF. GRISOOM. 



1. Force of vapor at different temperatures, - - 201 



2, 3, 4. Safety of steam boilers — Translation of the Mecanique 



Celeste — Germination upon mercury, - - 202 



5. 6, 7. Boring* for water — Preservation of iron from rust — 



Beet sugar, - - - - - - 203 



8, 9. Hydrophobia — Silicine — P. S. Bedford mineral springs, 204 



NUMBER II. 



Art. I. On the best method of obtaining and preserving Potas- 

 sium ; by L. D. Gale, M. D. Ass't to Prof Chem. Coll. 

 Phys. and Surg. New York, _ _ _ 205 



II. Instructions for collecting Insects for cabinets ; by M. 

 Theodore Roger. Translated from the French, by 

 Jacob Porter, M. D. - - - - 213 



III. On the Mineralogy and Geology of St. Lawrence County, 



New York ; by J. Fingh, F. B. S. &c. - - 220 



