via 



• CONTENTS. 



Page. 



6, 7. Vegetable Physiology, Circulation of sap — Motion of liv- 

 ing particles in all kinds of matter, - - 



8, 9. Large still — Production of magnetism by friction, 

 10, 11. Hay converted into asilicious glass by lightning — Flying 



in the air, ------ 



12. Formation of hail, - 



13, 14. Expansion of gases — Leonardi da Vinci, 



Oolite in situ, in Edenville, N. Y. 



Hints and Conjectures respecting some of the Causes of the 

 Earth's Magnetism ; by Prof. B. F. Joslin, of Union Col- 



393 

 394 



395 

 396 



397 

 398 



lege, N. Y. 



APPENDIX. 



ib. 



On the application of the principle of the galvanic multiplier 

 to electro-magnetic apparatus, and also to the developement 

 of great magnetic power in soft iron, with a small galvanic 

 element ; by Prof. Joseph Henry, of the Albany Academy, 400 



ERRATA, AND ALTERATIONS FROM MS. — VOL. XIX. 



Art. V. page 46, for C f whenever it occurs, read c'. mm 



" 49, 5th line from top, for 1, read — 1. 



Page 49,3d line from bottom, instead of " If the impulses act continually," sub- 

 stitute If the impulses are indefinitely small and act continually. 



Art. IX, page 61, first line, after have read not. 

 Pace 135, line 2d from top, for their read these. 



<< 



« 



<4 



CC 



136, 

 137, 



« 



<« 



Li 



14th from bottom, for of read to. 



15th from bottom, tor professedly read professionally. 



10th from bottom, for design read degree. 



