Aeronautics — Magnetism, #c. 173 



2. An unexceptionable opportunity was chosen on the 22d May to make 

 the following observations on the solar radiation. The bulb of the ther- 

 mometer was covered with black cloth. 



Hour. Sun. Shade. Hour. Sun. Shade. 



10 h 50' 96°" 51° 12 h 0' 1034° 60\* 



Maximum force of solar radiation 53°. A 



AERONAUTICS. 



11. On the origin of Air Balloons. — Mr G. Cumberland of Bristol, in a 

 paper on the origin of air balloons, published in the last Number of the 

 Quarterly Journal of Science, states it as " rather remarkable that so many 

 books have been published on the subject of balloons, and so much money 

 expended in useless experiments, to discover a method of guiding them with 

 precision, while no one that he knew of has as yet pointed out the origin of 

 the invention, which will be found copiously detailed, accompanied by a 

 figure explanatory, in a folio volume, dedicated to Leopold I. by Francesco 

 Lana a Jesuit of Brescia, MDCLXX." As the sole object of Mr Cumber- 

 land's paper seems to be to make known the claim of Father Lana, we beg 

 to inform him, that not only a description of Lana's Aeronautic vessel, 

 but also an Engraving of it, was published nearly twenty years ago in the 

 article Aeronautics, in the Edinburgh Encyclopaedia, vol. i. p. 165, 

 and Plate III. fig. 1. 



MAGNETISM. 



12. Professor Hansteens Magnetic Journey to Siberia-'— in a letter 

 which we have just received from Professor Hansteen he expresses his 

 anxiety of carrying into effect our wishes of obtaining the mean tempera- 

 ture of places related to the Asiatic Pole of maximum cold. " From To- 

 bolsk, says he, I shall descend the river Obi to Beresov, and perhaps to the 

 Gulf of the Polar Ocean, where this river falls into the sea ; and it will 

 give me great pleasure during this excursion to the north, as well as during 

 the whole journey, to make every sort of useful observation." 



II. CHEMISTRY. 



13. Expansion of crystallized bodies by heat. Professor Mitscherlich 

 has published a paper on this subject in " PoggendorfFs Annalen der Phy- 

 sik u. Chemie," vol. x. p. 137, &c. The results of the observations of 

 this celebrated chemist are the following : He has measured some crystal- 

 lized minerals in the temperature of a room, and then in hot mercury. 



