Chemical Science, 466 



heated during the absence of the family, had at last caught 

 fire, and was totally consumed, together with the barrel which 

 contained it, nothing remaining but the iron hoops and a few 

 pieces of charcoal. It is presumed that the meal had been 

 somewhat moist, and that it had heated precisely in the same 

 way that hay does when stacked moist. The kitchen did not 

 seem to be unusually damp on the day when the house was 

 opened. Dr. Thomson remarks, that the great avidity which 

 oatmeal has for moisture, and the heat generated by the ab- 

 sorption of it, must be familiar to every one who has been in 

 the habit of seeing oatmeal. Mr. Leslie has taken advantage of 

 its avidity for moisture, and has applied it in the place of sul- 

 phuric acid in his well-known and ingenious process of freezing 

 in the exhausted receiver of the air-pump. — Annals of Philoso- 

 •phyy vol. xvi., p. 390. 



9. Effects "produced by Time on Wood buried in the Ground, — 

 Whilst cutting and carrying away a part of Castle-Field, near 

 Manchester, an ancient well was discovered about four yards 

 below the level of the field. It was square and formed of four 

 upright posts driven at the angles into the clay, and closed in 

 by other logs of wood, placed one upon another on the outside, 

 so as to form a kind of chest which was floored with the same 

 material. The logs were rudely hewn, had never been sawn, 

 and were five or six inches square. The upper logs were level 

 with the top surface of a bed of clay by which the well was 

 surrounded, and into which the timber was inserted. The 

 wood, when first discovered, had little more consistency than 

 paste, but, on its exposure to the air, became much harder and 

 more wood-like; it. was perfectly black, and had so much of a 

 coal-like appearance as to favour the theory of those who sup- 

 pose that pit-coal was originally a vegetable substance. At the 

 bottom of the well some large stones, such as in this neigh- 

 bourhood are called bowlers, were found. They were black 

 and dirty as though thoy had been taken from a sewer, and the 

 clay which adhered to the timber had also changed its colour 

 from the rusty iron tinge of the native clay to the appearance 



