440 
The Ohio Naturalist. 
[Vol. XV, No. 4, 
insured and with a total risk of not far from $300,000,000, most 
of them reporting for the years 1912 and 1913, quite a number 
covering the past 5 years, and 5 for between 13 and 25 years, 
with not one building ever burned or damaged to any extent by 
lightning that had a lightning rod on it. 
These findings of the efficacy of the lightning rod in preventing 
lightning stroke are contrary to the general opinion, but they 
substatiate those by Professor W. H. Day, of the Ontario Agri¬ 
cultural College, as published in their Bulletin 220. His inquiry 
covered Ontario, Iowa and Michigan, and included the records 
for several years and found the efficacy of a lightning rod in 
preventing lightning stroke to be from 92% to 99.9%. 
Damage to Rodded Buildings. —In addition to actually 
preventing the lightning stroke, the properly installed lightning 
rod is of very great value in preventing damage to a building 
when it is struck by lightning. 
The table in this report shows that the total claims paid on 
farm buildings due to lightning in 1912 and 1913, was $336,171. 
Inasmuch as 31% of the buildings insured by these companies were 
rodded, we would expect a loss on rodded buildings of 31% of 
$336,171, or $104,213, but as a matter of fact the total claims 
paid by these companies by lightning damage on rodded buildings 
during the two years was only $12,788. In other words the 
actual loss was only 12% of what would have occurred if the 
lightning rods did not serve as a protection. 
The total number of buildings burned by lightning in 1912 and 
1913 as reported by these companies was 407, and of these only 9 
were equipped with lightning rods, or only 2%. Of those struck 
that had rods only 5% were burned and the other 95% simply 
damaged. Showing that the danger of a building being burned by 
lightning that is equipped with lightning rods is exceedingly 
slight. 
A further study of the reports sent shows that where the 
buildings were struck by lightning and damaged, but not burned 
down the average damage per building was less than $10 on those 
equipped with lightning rods and very nearly $200 per building 
where not equipped with lightning reds. 
Imperfect Rodding. —In some of the cases where rodded 
buildings were burned or damaged by lightning, the rods were 
recently installed and appeared to be in good condition. But in a 
large number of cases the rods were known to have been in poor 
condition or improperly installed. Some of the rods were old and 
defective, some not properly grounded, in some cases the lightning 
entered the building on a clothesline, in others the lightning 
struck a nearby building and the fire was communicated to the 
rodded one. 
