8 DEPARTMENTAL REPORTS. 



spite of a bombardment by saying that the cannon was not large 

 enough or the powder charge sufficiently heavj 7 , and declare that the 

 hailstorm was far less severe than it would otherwise have been. How 

 is one either to prove or disprove such statements ? 



It is true that many important discoveries have been made by 

 experiments that were conducted contrary to scientific theories, and 

 in the matter under discussion it is not our intention to overweight 

 the scientist or to underestimate the practical investigator, but 

 unquestioned facts and not explanations must be the proof of results. 

 Scientists both in America and in Europe declare that hailstorms 

 can not be prevented by the use of cannon and explosives of even 

 greater power than have been used or that it is possible for man to 

 use, and they base their belief on such knowledge of the forces of 

 nature as science has revealed. Those opposed attempt to break 

 down the scientists' argument by declaring that no one has yet satis- 

 factorily explained the processes of hail formation. This is true to a 

 certain extent, but enough is known upon which to base a logical 

 opinion. 



But there are other reasons for believing that the use of cannon and 

 explosives in preventing hailstorms is not effective. Mr. Stiger, one 

 of the inventors of the apparatus in use, claims that hail is formed in 

 quiet spots in the atmosphere, where atmospheric moisture crystallizes 

 out in large crystals in a manner analogous to the formation of large 

 crystals of salt in liquid solution. I agree with Professor Abbe that 

 there are no such quiet spots in the atmosphere, and hailstones are not 

 crystals, but masses of ice with only a partial crystalline structure. 

 Even the perfect crystals of the snowflake are formed in the midst of 

 rapidly moving air. Hailstorms are generally local and very erratic. 

 Some have maintained that they are controlled by the hills or the con- 

 tour of the ground or by the presence of forests and lakes, and this 

 may be true to a certain degree; but, practically, the whole question 

 is one of ascending and descending currents that characterize whirl- 

 winds and thunderstorms. i 



Several thousand shooting stations have been established imltaly 

 and France during the past two years, but reports received from them 

 give no definite data in support of the success of the experiments, 

 although there is no doubt that the cannonading is believed to be 

 effectual by the farmers who do the work. Waves of irrational 

 enthusiasm sometimes sweep over a community, only to be regretted 

 in subsequent years when calmer judgment has come to prevail. We 

 have but to remember the experience of our own country only a few 

 years ago with the rain makers, and how firm was the belief of thou- 

 sands of people in the subarid and arid regions of the West that the 

 use of powerful explosives would produce rainfall. 



Thousands of dollars were expended in these experiments before 

 the absurdity of the claim was demonstrated. It is a fact worthy of 

 remark that the hail shooters are now using practically the same 

 methods to dissipate the clouds that the rain makers used to produce 

 them. Time and experiment will probably demonstrate that hail 

 X>revention by such means is as impracticable as rain production. 

 The fact that 15,000 or 20,000 shooting stations have been established 

 is of itself no argument as to the efficiency of the process. One 

 might as well argue that the moon really affects the weather because 

 a million people believe it and can prove it — to their own satisfaction. 



A knowledge of the exact truth on any question of natural science 



