16 



of his great service to the navy, and thereby to the British Empire. Throughout 

 England, Germany and France lightning rods became the subject of study, and 

 many buildings, especially costly ones like the great churches and cathedrals, were 

 protected by lightning rods, so that the loss to buildings of this kind by lightning 

 was almost completely overcome. This extensive use of the lightning rod in Europe, 

 together with continued study in America, has had the effect here of drawing atten- 

 tion again to the subject. 



In America the one man who has done more than perhaps any other to bring 

 lightning rods again into favour is Mr. West Dodd, of Des Moines, Iowa. A man 

 of great energy and scientific insight, he took up the lightning rod question twenty- 

 five years or more ago, when rods were in disrepute, and pursued it with such 

 tenacity and skill that he has overcome a hostile public sentiment and convinced 

 the people of the Middle Western States that lightning rods are an unqualified 

 success. His own State of loAva reports 50 per cent, of its farm buildings rodded. 



Fig. 19. — The electrical machine as Fig. 20. — A toy house with metal chim- 



modified by Mr. West Dodd for demon- ney, screen door, eave-trough and bal- 

 strating the thunderstorm. Note earth cony is set on earth plate and machine 

 plate E. and cloud plate C. turned. Note flash to chimney and 



sparks down screen door — ^the door is con- 

 structed with air-gaps, in jumping which 

 the current causes sparks. Dangerous to 

 stand by screen door during thunder- 

 storm. 



perhaps the highest percentage of any similar area in the world. Motoring through 

 that state for a distance of fifty or sixty miles, the writer verified this percentage 

 by actual count. In his work Mr. Dodd adapted the electrical machine to demon- 

 strate the thunderstorm and the lightning stroke, and then used toy barns, houses, 

 animals and rods to demonstrate the phenomena of lightning and the efficacy of 

 lightning rods. With this equipment he appeared before the insurance companies 

 of Iowa and other states from time to time, and demonstrated scientifically that 

 rods must be effective. His teaching bore fruit in numerous companies granting 

 reduced rates on properly rodded buildings. 



The Electrical Machine Modified to Eepresent a Thunderstorm, 



^ Mr. Dodd attached a metallic plate to the negative side of the machine: to the 

 positive side another plate which hangs a few inches above the first one. The lower 

 plate represents the earth, and the upper one the cloud. (Fig. 19.) 



