Two years ago the cities in England and Scntlaifd wr( 1j|r srooJw-Tt-TVarr^ owing to the dense volumes of smoke which filled the atmosphere by the use of bituminoas coal. The fields of grain were black in appearance from the same cause, and the hedges were in the like condition. Now all is changed ; the sky is no longer like a smoke-house: the rains descend in clear streams, not in inky rivulets ; the houses begin to look as it their faces were washed, and the hedges begin to wear their old dark green appearance. All this has been accomplished by an Act of Parliament making it penal tor factories to let their smoke escape The smoke is all burned by simple contrivances of furnaces, among which " Juke's," which was illustrated in last volume of the Scientific American, is very conspicuous. A Commission of Government first established that the burning of smoke was perfectly practicable, and Parliament then enforced the fact by law. The factory and mill owners soon found out how to fullfil the conditions of this law, and the result is, they save a great deal of fuel by the operation. Like many other good things, this important improvement at first met with a great deal of opposition; there are some men who cannot judge when a good turn is done to them, and we can say that this is true in jespect to many useful inventions.