Show gallantryGhat What a Cold Slave Is Here is an explanation of something not generally known A cold wave as defined by Professor T Russell is a fall of temperature tem-perature in twentyfour hours of 20 degs over an area of 50000 square miles the temperature in some part of this area descending de-scending to 36 degs Between 1680 and 1S90 no less than 501 cold waves were recorded in the United States In the great cold wave of Jan 1718S2 the fall of 20 degs extended over an area of 1101 square miles and the fall of 10 degs included an area of 2029000 square miles In six cold waves of he ten years the area of the fall of 20 degs was more than a million square miles Cold waves follow a day after an area of low pressure or occur to the southeast south-east of an area of high pressure attaining their greatest extent when both conditions are present together They occur only however in the presence of an area of high or low pressure fI iieo |