THE CULTIVATOR. 
Fee. 
84 
Lightning Rods—Protection of Barns, &o. 
Eds. Cultivator —‘The common opinion is, that a 
lightning rod attached to a barn or other building, is in¬ 
tended to receive the shaft of lightning after it has left 
the cloud, and conduct it harmlessly to the ground. This 
it may do sometimes, but I am clearly of the ( opinion 
that this is the smallest service that it renders. I pro¬ 
pose in this paper, to enter into the subject at large, 
and to examine it thoroughly, with a view to its more 
clear elucidation, for the benefit of farmers and others. 
The cause of a thunder storm, is a disturbance of the 
equilibrium of the electricity of the earth and the at¬ 
mosphere. Thus, if a cloud be more highly charged with 
electricity than the earth beneath it, there is a disturbance 
of the equilibrium, the cloud becomes positively and the 
earth negatively charged, in relation to each other, and 
an explosion or discharge from the cloud to the earth will 
necessarily take place, unless some medium be provided 
for conducting the excess of the fluid from the cloud to 
the earth. A damp atmosphere between the cloud and 
the earth, connecting them, will accomplish this. And 
in all cases of this disturbance, there must necessarily be 
a stratum of very dry atmosphere between the cloud and 
the earth. Let us suppose a storm approaching. A 
heavy black cloud approaches rapidly from the north¬ 
west. It is highly charged with electricity. Everybody 
expects a thunder storm. Now, the question is, how can 
this threatening storm be prevented ? I believe it can be 
in all cases. The prime conductor of a powerful electri¬ 
cal machine, represents an over charged cloud. A pow¬ 
erfully charged Leyden jar, represents the same. Now, 
when either of these are fully charged, if you hold with 
your fingers the point of a needle towards them, you will 
gradually, and insensibly,discharge them. If you are smok¬ 
ing a segar, and approach the burning end of it near the 
jar of the conductor, you will effectually discharge them 
through your own body, unfelt. Whereas, if you ap¬ 
proach either with a blunt object, say the knuckle of the 
finger, you will in the case of the conductor, receive a 
sharp spark—a miniature streak of lightning; in the case 
of the Leyden jar, a violent shock. On this principle I 
have taught many a little girl to play tricks with the pow¬ 
erful electrical machines at the museums. I direct them 
to hold a needle, or even a pin, between the knuckles of 
the fingers, the point only projecting to a level with the 
apex of the knuckles, so that it will not be seen; and as 
the operator turns his crank to get up a charge, hold the 
knuckles within an inch or two of the prime conductor. 
If she do this, in vain shall the operator strive and labor 
to get up a charge. If she allows him to get the conduc¬ 
tor fully charged, and then hold her knuckles, with the 
pin between them, to the prime conductor, say within an 
inch, it will be immediate^ discharged—and the operator 
is struck with wonderment, being unable to account for 
the failure of his experiments. So, also, shut the fingers 
of the hand closely, and let the knuckles represent a row 
of houses. Place a sharp pointed pin or needle between 
the two middle knuckles, the point not higher than the 
knuckles. Now hold the knuckles towards the prime con¬ 
ductor, approaching ever so closely, and there will be no 
spark seen,however vigorously the machine may be work¬ 
ed; but, without withdrawing the knuckles, merely relax 
them so as to drop the pin, and instantly the knuckles 
will be struck by the spark. You may use the pin in any 
way j r ou please, and you cannot attract to it a spark; 
but you can discharge the prime conductor of the Ley¬ 
den jar of all its excess of electricity, as before described. 
In these cases the excess of electricity passes over the 
point of the pin, and the body of the person holding it, 
unseen and unfelt. When these experiments are perform¬ 
ed in a very dark place, the point of the pin is seen to be 
very luminous while the conductor is being discharged. 
Now, what is expected to be elucidated by these expe¬ 
riments in relation to the subject of lightning rods, is 
this:—The great prime object of a lightning rod, is to 
form a medium through which the equilibrium of the 
electrical state of the earth and air may be re-established, 
or its disturbance prevented. Suppose a cloud to be ap¬ 
proaching, heavily charged with electricity, directly over 
a barn filled with the fresh harvest. If that barn be pro¬ 
vided with a good lightning rod, it may by chance be pro¬ 
tected by the rod receiving the shaft as it descends. But 
suppose several good lightning rods were erected at a 
distance to windward of the barn, they wrnuld effectually 
discharge the cloud of its electricity before it reached the 
barn. And here permit me to remark, that I believe a 
lightning rod affords more protection to some neighbor’s 
buildings to the leward of it, than it does to that on 
which it is situated. According to my ideas of the laws 
of electricity, the proper protection of farm buildings 
should consist in the erection of lightning rods on several 
very high trees, or other elevated objects at a distance 
of at least a quarter of a mile from the buildings, in such 
directions from them as such storms usually come from, 
say, north, north-west, west, south-w^est, south and south¬ 
east. I would also erect lightning rods on all the buildings, 
for special protection. If a dozen lightning rods were thus 
erected on a farm, and properly adjusted, I do not see 
how it w'ould be possible for the buildings on the farm, or 
anything else, to be struck with lightning. 
The reason why so many barns are struck by lightning 
every summer,is very obvious. W e rarely hear of an empty 
barn being struck. Barns filled with the freshly gather¬ 
ed harvest, are the usual victims. The reason is, there 
is a large column of vapor passing upward from the barn, 
and presenting to the over-charged cloud a large blunt 
point of attraction. This column reaches an altitude 
much higher than any lightning rod can do. It is a very 
powerful attractor of electricity. (This may also be il¬ 
lustrated by holding the mouth within a couple of inches 
of the prime conductor of an electrical machine, and 
breathing upon the conductor, which will immediately 
discharge it, insensibly to the operator.) Hence, as the 
cloud arrives over the barn, with its load of electricity, 
the column of vapor being the nearest object of attrac¬ 
tion, causes an explosion, or streaks of lightning. If this 
column could have been prepared with a sharp metallic 
point, it would have discharged the cloud without an ex¬ 
plosion. In this connection it becomes important to ob¬ 
serve that the grain and hay should be made as dry as 
possible before it is placed in the barn or large stacks. 
If it were perfectly dry, the barn w r ould be in no more 
danger from lightning than any other building. 
The above theory applies with equal force to all cities 
and villages. It is believed that one hundred lightning 
rods properly arranged, (and of this we will speak pre¬ 
sently,) would effectually protect the whole city of New- 
York against lightning. Suppose such should be erected 
on Long-Island, on the heigts of Brooklyn, of Hoboken, 
on all elevated places around the northern suburbs,at suit¬ 
able distances and throughout the city, especially upon all 
high buildings,steeples,towers,&c.? If such were done I do 
not see how it is possible for any house in that city, or 
anything else to be struck by lightning, because every 
cloud, from whatever quarter it might approach, would 
be effectually deprived of all superabundant electricity be¬ 
fore it could reach the city. These rods would not only 
form mediums for equalizing the electricity in the case' 
of overcharged clouds, when the earth is in the condi¬ 
tion of a negative to the positive cloud, but in the re¬ 
verse condition, when the earth is positive and the at¬ 
mosphere or cloud, negative. They would form conduc¬ 
tors equally as well one way as the other. I know of 
no outlay that a city or village could make, that would be 
more judicious than this; and the farmer, certainly, can¬ 
not safely dispense with it. But the position of the rods 
is not the only point of importance. The manner of 
their arrangement is essentially the point of greatest mo¬ 
ment, and we will now proceed to discuss that. 
A lightning rod,—its material and manner of construc¬ 
tion or erection, is the simplest thing in nature or me- 
