THE FARMER AT HOME. U5 



d >es great mischief by exploding whenever it comes in contact with 

 tleir lights. Carbonic acid gas is generated in large quantities in 

 1] e vats of cider distilleries, where a small quantity of the liquor re- 

 11 ains for any time ; or in brewers' vats, in which acetous fermenta- 

 li}n is allowed. Numerous deaths occur yearly from the operation of 

 thia- gas, and farmers and others, who are particularly exposed in 

 <' eaning wells, should always take proper precautions. Where it ex- 

 i?ts in large quantities, it extinguishes flame ; and, hence we are for- 

 tunately provided with the means of ascertaining its presence. No 

 o le, therefore, should venture a descent into any of the places named 

 without first lowering a candle or a lamp. If the flame is extin- 

 guished, life would also be put in peril. If it is not extinguished, one 

 a lay descend safely. 



DARK DAYS. The "Rev. Mr. Sterling gives an account (as 

 published in the Philosophical Transactions in England,) of a dark- 

 ness of six or eight hours at Detroit, in North America, on the nine- 

 teeth of October, 1762, in which the sun appeared as red as blood, 

 and thrice its usual size ; some rain falling, covered white paper with 

 dark drops, like sulphur or dirt, which burnt like wet gunpowder, and 

 the air had a very sulphureous smell. He supposes this to have been 

 emitted from some distant earthquake or volcano. Dr. Darwin adds, 

 that a dry fog (somewhat similar to the appearance at Detroit) cov- 

 ered most parts of Europe, for many weeks, in the summer of 1780, 

 which was supposed to have had a volcanic origin, as it succeeded 

 the violent eruption of Mount Hecla. It is remarkable that the same 

 fear which Dr. Darwin mentions, that is, on the nineteenth of May, 

 m the afternoon, 1780, a surprising darkness overspread New Eng- 

 land. For several days preceding this darkness, the sun appeared 

 from morning to night, unusually large, and nearly of the color of 

 blood ; and this was its appearance during the forenoon of the mem- 

 orable nineteeth of May. Early in the afternoon, the sun was totally 

 obscured, and all objects had a yellowish or brassy hue. The dark- 

 ness increased gradually till about three or four o'clock, when the 

 fowls went to roost, candles were necessarily lighted in dwelling- 

 houses, and it seemed to be night. During the progress of this won- 

 derful fog, some scattering drops of rain fell, attended, as it was then 

 said, with a blackish powder that tinged the substances which were 

 touched by it. 



DARKNESS. Means the absence or the want of light. In 

 common language we consider ourselves as being in darkness, when- 

 ever objects that are pretty near to us, cannot be distinguished from 

 each other ; but perfect darkness does not easily occur ; arid it is ow- 

 ing to this that several animals can see in what we call darkness, 

 viz., the eyes of those animals are so formed as to be able to see with 

 very little light. But it appears from the experiments of M. le Cat 

 and others, that no animal cart see in perfect darkness where no light 



