170 
Mr. Leigh suggested that the evolution of nitrogen in 
volcanic eruptions might he due to a reaction similar to that 
described in Dr. Pauli’s Paper. 
Mr. Spence and Dr. Calvert explained the processes 
employed in manufacturing caustic soda for commercial 
purposes. Mr. Spence also described the beds of nitrate of 
soda in Southern Peru and Northern Chili, from which 
nearly all the commercial nitrate of soda is obtained. 
Mr. Baxendell believed that the preservation of the 
nitrate of soda in these beds had been due to the dryness of 
the climate, as rain rarely falls in the region in which they 
* 
are found. Had the climate been a rainy one, he believes 
the deposits of nitrate of soda would long since have been 
washed away. 
Mr. Baxendell communicated an observation of Saturn 
which he had lately made. Owing to the relative positions 
of the sun and earth, with respect to the plane of the ring 
of Saturn, the ring ought now to be quite invisible in 
telescopes of moderate power ; but on the night of the 1 8th 
instant he had seen very distinctly a portion of the ring on 
the following or east side of the planet. The telescope 
used Avas Mr. Worthington’s achromatic of five inches 
aperture. He also stated that from observations made by 
himself and Mr. Williamson, in 1848, he had been led to 
believe that the plane of the ring Avas not exactly parallel 
to the dark belts on the body of the planet. As several 
members of the Society noAv possess good telescopes, it is 
to be hoped they Avill direct their attention to this interest- 
ing point, and favour the Society Avitli the results of their 
observations. 
A Paper, “ On the Convective Equilibrium of Tempera- 
ture in the Atmosphere,” by Professor Wm. Thomson, LL.D., 
F.R.S., &c., Avas read by Dr. Joule. 
