Show DO DOWN N IN THE EARTH Temperature Varies In Different Parts of cf the World in Son the report of the last coal commission commission com com- mission the conclusion is arrived at that at a depth of feet the temperature temperature temperature tem tem- of the earth would amount to 98 degrees Fahrenheit but it was considered that a depth of at least feet might ultimately be reached In coal mining The rate of increase the commissioners thought might for ordinary cases be assumed to be one degree Fahrenheit for every 60 feet but it is really impossible to give any fixed rate of increase The report of the British association association association tion committee on underground temperatures temperatures temperatures tem tem- during the last thirty years tends to show not only that the temperature temperature temperature tem tem- gradient varies considerably considerably- In different localities but that it is not easy to deduce a fixed law of increase increase increase in in- crease applicable to all cases In some parts of western America the heat at feet is almost unbearable while at the copper mine In north Michigan there is a rise of only four degrees Fahrenheit in a depth of feet although although al al- though no no artificial ventilation is resorted re re- resorted sorted to The temperature of the coal on discovery discovery discovery dis dis- covery at the colliery In Lancashire was stated by the management management management man man- to be 93 degrees Fahrenheit but it afterward fell to 63 degrees Fahrenheit Engineering Engineering Magazine |