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very considerable. In Italy the damage to vineyards annually 

 caused by hail is estimated at over 4,000,000. In 1880 an 

 Italian savant, Professor Bombicci of Bologna, observed that 

 showers of rain were most frequent in those places where 

 gun practice shook the air and filled it with smoke. Then 

 followed the well known American experiments (which have 

 however led to no practical results) for artificially producing 

 rain in a cloudless sky. In one direction Professor Bombicci's 

 researches have led to a very practical result. In 1896 

 in Styria (Austria), a progressive vinegrower, Burgomister 

 Stieger, started shooting with cannons against approaching 

 storm clouds. He established shooting stations on the hills 

 surrounding his vineyards at an altitude of from 300 to 800 

 yards. At every station he had from 5 to 6 mortars in a 

 wooden hut, so that shooting could be proceeded with even 

 during rain. His mortars are 18 inches long and they weigh 

 about 160 Ibs. each with a 3 centimetre chamber. He loads 

 them with about 5 oz. of miners' powder. The clouds either 

 disperse or come down in the form of rain and he has alto- 

 gether avoided hail by this means. His example has been 

 largely followed in Austria and Italy. There are now about 

 600 hail preventing stations in Italy. 



no. The weather chart. The agriculturist should be 

 familiar with the reading of the weather-chart. The curved 

 dotted lines that one sees on weather-charts, called isobars, 

 are imaginary lines, each connecting all those places which 

 have at a given time the same barometric pressure. From a 

 number of these isobars on a chart one can see at a glance 

 the nature of the distribution of atmospheric pressure over 

 a country at any given time. The Meteorological Depart- 

 ment issues these charts every morning. The difference of 

 pressure between one isobar and the next is called the 

 gradient. A gradient of 4, means, that over a distance of i 

 degree or 60 miles, the barometer has risen by -^-^ or ^ ths 

 of an inch. When the isobars are drawn close to one another 

 they indicate high or steep gradient ; when they are wider 

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