1848. 
THE CULTIVATOR 
19 
have cost me more than that in my own shop, only ra¬ 
ting- labor at 75 cts. per day. 
If manufacturers wish to sell plows South, they must 
make their castings of the best iron; chill all wearing 
surfaces; make them higher in the beam, and plows to 
cost $5—this is price enough for a No. 1, one horse 
plow. Some lands- want a mould board like the old 
Carey plow, standing up and bluff to their work, whilst 
others want only enough curve to let the earth fall 
over. M. W. Philips. Edwards, Miss, April 23. 
Coal Grinder and Soil Presser. 
Charcoal would have been better known and more 
extensively used as a fertilizer, if the expense and in¬ 
convenience of its application had been less. It has 
been sufficiently tested, however, to establish the fact, 
that it is one of the most useful applications to the 
greatest variety of soils, that has ever been known; it 
only remains for us to get up some cheap and expedi¬ 
tious wav of powdering and applying it; for which pur¬ 
pose the machine represented in the above cut is inten¬ 
ded. It shows a side view of a common roller for pres¬ 
sing the soil, with the addition of a small grooved cy¬ 
linder so geared with the roller by the cog wheels re¬ 
presented, as to cause the surface of the roller to move 
much faster than that of the cylinder, thereby adding to 
the crushing movement, that of grinding, which toge¬ 
ther, pulverize the coal and drop it in front of the roller. 
By this operation the roller is dusted and kept free from 
the adhesion of any earth, and the coal is evenly distri¬ 
buted and pressed into the soil, so that the wind will 
not blow all the best of it away. Those who believe in 
applying charcoal to the surface after sowing, will see the 
utility of this machine. Dean. Lyonsdale, N. Y., 
April 22, 1848. 
Value of Guano. 
As a top dressing for grass, I have never yet found 
any thing superior to guano, especially directly after 
mowing or close pasturing. Spread broadcast from 
250 to 500 lbs. per acre, according to the fertility of 
the soil; and if rain or heavy dew soon follows, the ef¬ 
fect will be surprising. If the grass be cut or depas¬ 
tured early in the season, say by the last of June or 
fore part of July, I have repeatedly noticed that the 
guanoed patches produced as great a second growth as 
that of the first. This is a matter of no small consi¬ 
deration to those who have only a small quantity of land, 
and are desirous that it should yield the greatest possi¬ 
ble product. Another consideration, guano gives the 
turf a greener and richer appearance than most kinds 
of manure ; and will frequently bring in other highly 
nutritious grasses, which may not have made their ap¬ 
pearance in the field for years before. 
For Turneps, Guano is a very valuable manure, and 
has the merit of being extremely disagreeable to the 
fly. After the ground is prepared, spread the same 
quantity broadcast as upon grass, either before or after 
the turnep seed is sown, and then smooth over with a 
fine harrow, bush or roller, or with all three, as may be 
most convenient. Some prefer to apply only half the quan¬ 
tity of guano at the time of sowing the seed, and add the 
other half when the turnep plant is in its first leaf. 
They think this method a better guard against the fly, 
and that the guano proves equally beneficial. 
For Corn. —At the last hoeing, apply a heaping ta¬ 
ble spoonful around each hill, about six inches from the 
stalks, and with the hoe mix it with the soil. It is ve* 
ry effectual in assisting the ears of corn to fill out well 
with grain; and it adds also somewhat to the growth 
and nutriment of the stalk. 
For Wheat and Rye. —As a top dressing for these 
crops, at the time of or after sowing, guano has pro¬ 
ved itself equal to the best of manures. 
Strawberries and other f ruits delight in guano. It 
increases the size of fruit of all kinds, and adds much 
to its delicacy and flavor. 
For Various other Crops, Guano is highly recom¬ 
mended by our most experienced farmers and garden¬ 
ers, when a large quick growth is desired. 
It is upwards of twenty years since guano was first 
introduced into the United States, and for the past five 
years it has been very extensively used and highly ap¬ 
proved of by the farmers and gardeners in the neigh¬ 
borhood of Boston, New-York, Philadelphia, Baltimore, 
Norfolk, Charleston and New-Orleans. A. B. Allen. 
New-York, June 13, 1848. 
[For price of guano, which is quite low, see adver¬ 
tisement of A. B. Allen & Co., 189 & 191 Water St., 
New-York.] ___ 
Lightning Hods. 
The electric fluid, whose passage through the air is 
commonly called a flash of lightning, has a stronger 
affinity for some substances than for others. This is 
easily shown with a common electrical machine; for 
having obtained a sufficient charge for our purpose, on 
presenting a rod of copper in one hand and a rod of 
glass in the other, at equal distances, the discharge 
will be found to take place on the copper and not on the 
glasss one—hence we have what are called conductors 
and non-conductors. Electricity passes with greater 
or less facility, according as the object with which it is 
brought in contact, possesses affinity for the fluid—or 
according to its conducting power. Hence those things 
which stand low in the scale, or non-conductors, afford 
an almost impassable barrier to electricity, and are com¬ 
monly shattered to pieces in its passage. 
To apply these facts to the subject of protecting 
buildings by lightning rods: suppose a discharge about 
to take place in close proximity to a house on which is 
affixed a lightning rod; by reason of the attraction of 
the rod, the fluid is turned out of its course to the 
building, (which is a non-conductor,) and passes down 
the metal into the ground—leaving behind none of 
those fearful appearances which would otherwise have, 
marked its passage. Here, then, we see that the 
greater the difference between the conducting power 
of the building and the material of which the rod is 
composed, the greater will be the protection secured. 
Iron and copper are the metals which are found to 
answer the purpose best; and although 'copper is the 
most powerful conductor, yet by reason of its high 
price, compared with iron, the latter is commonly used. 
The next thing td be considered is the dimensions of 
the rod. And first, as to length or height; suppose a 
rod twenty feet high, to be placed exactly perpendicular 
to the ground; then with a radius of forty feet, describe a 
circle whose centre shall be the spot penetrated by the 
rod. The diameter of this circle will be eighty feet. 
Now each and every object within this circle, which 
does not project out of an imaginary line drawn from 
the top of the rod to the circumference of the circle, 
will be found to be fully and amply protected. The 
law may be said to be, that a lightning rod will protect 
everything placed within the circumference of a circle 
describing it, with a radius twice the perpendicular 
