Miscellanies. 371 



the necessity of keeping the windows down. It may also be very 

 conveniently applied to stage coaches travelling at night, and in the 

 vicinity of marshes. To give additional security, the sash may be 

 so constructed as to consist of two sheets of wire gauze, half an inch 

 or more apart, or made in such manner as to be placed up at night 

 and removed during the day. It is certainly well worth the attention 

 of the scientific. 



9. 0)1 the Heating of Water; by Dr. E. Emmons. 

 It is familiarly known, that the upper surface of heating water is 

 hotter than the bottom, and that even ice may remain at the bottom, 

 while the water near the surface would be quite uncomfortable to 

 the hand. Now the experiments of Peron prove the water of the 

 ocean to be in the same condition as water heating in a furnace j viz. 

 with the bottom the coldest and the upper surface the warmest, while 

 circumstances are known to depend on the ascent of heated parti- 

 cles of water to the surface, and the sinking of the colder to the 

 bottom. Now, until it is shown that a different effect would follow, 

 from heating the ocean at the bottom, than what takes place in our cu- 

 linary operations, I shall consider the experiment of Peron as mis- 

 applied in the article I have noticed. Fearing that I may be mista- 

 ken in my views, I will respectfully request Mr. T. to consider the sub- 

 ject farther and give his opinion on the heating of water at vast depths 

 and under great pressure ; and show, if possible, that the heated par- 

 ticles of water would not tend to the surface, but be confined to the 

 bottom, forming there a stratum of hot water more dense than marble. 

 If however the heating of the ocean at the bottom would be attend- 

 ed with the same circumstances as the heating of a kettle in a fur- 

 nace, then the experiments of Peron instead of going to disprove 

 the theory of Cordier, would in the view of some, furnish argu- 

 ments in favor of it, for it is known that the ocean continually gives 

 off caloric to the surrounding medium, and what source for a continu- 

 al supply of it can be found, nearer at hand, than the interior heat of 

 the earth? 



10. On the Carbonization of Lignite. — The prevailing theories 

 on the formation of Lignite are two, 1st, that which ascribes its for- 

 mation to fire, 2d, that which gives to water the agency of effecting 

 this change on vegetable matter. The latter was suggested by Dr. 

 MacCuUoch, and has been adopted by Conybeare and Phillips in the 



