Show pure air from a coal fire I 1 A discovery having an important bearing upon the arto art and tures tares has recently ben been made by william A gibbs of essex the discovery is that perfectly pure air can be produced from the combustion of f coal the arrangement for effecting this re sult suit is very simple it consists of a brick chamber about five feet long by two feet wide and two feet nigh high built upon the ground atone at one end Is aneed a feed chamber and a fuel chamber and g at the other a powerful exhaust and blast fan placed immediately between the chamber anber and blast alist fan are baffle plates splitting plates a standing bridge with P perforations f ora ions at the back and a hanging hangin 9 b andge g e with pe perforations at the front there are also several calef carefully ally inlets to supply the exact quantity of gir air requisite to perfect combustion this exact apportionment of ef the theair fair constitutes one of the main poin cointa I 1 of success and it is the one which I 1 amri mr gibbs found the most difficult to 10 mine once known however the law of proportion between air avid and fire is of course easily maintained another point having a very important bearing on the result is iq the eat exact relative proportion of the to the feed chamber and of both to volume of air drawn per minute by the tan inn this also being ascertained at after r many failures is now a fixed instead ins of a doubtful quantity given th these e proportions and some others of minor importance the result is distinctly curious issuing f from rom a fan mouth twelve inches in diameter comes rushing a column of hot air mark marking lugon on the pyrometer at its exit ae a steady uniform temperature of degrees fahrenheit not a trace of smoke or fume is visible to the eye i not a taint of any kind is perceptible to the uste taste or smell Itan standing Standi cling ag as we did in the range of ef this with the blast full fall in the face e the beat is of course excessive buethe e stream of air is perfectly pure save in the matter of temperature it affects nether leiher the eyes the throat nor ohp nostrils As asa a proof of nis some tea which had been salu rated with hot water was placed iw itil the hot air current carrent and when re dried was pronounced by an expert tu to be wholly free from any imparted taint or taste la in order to show the character of the products of combustion before bein being 9 submitted to the fiery ordeal the fan was stopped and a dense cloud of thick smoke rose up from the coal iu in tue feed chamber charged with suffocating fumes on restarting tinz the fan it WAS quietly drawn in again but not a sign of it appeared at the exit from the fan and the air when inhaled was as pure pare as ever it would be interesting to know the rationale odthe of the process by means of which allene varied products from coal combustion are so corn coin plemely destroyed mr gibbs suggests that the water contained in the coal if is decomposed into oxygen and hydrogen and that the hydrogen in burning adds to the heat beat of th resultant air while the oxygen fein reinforced forced as it is by that obtained irom rom the large volumes of fresh air admitted at the various inlets ft decomposes composes and all these products but whatever the theory may be the fact remains that it is not only possible but easy and economical to obtain the utmost amount of heat from coal without any deterioration of the atmosphere the success attained by mr gibbs naturally suggests the application of the principle in hi many important directions in connection with the industrial ats as as well a as for steam raising pur par poses and for domestic use by tae suppression ot open fires in stoves london londen times |