24 
EXPERIMENTS WITH GUANO. 
ically, from a consideration of the analysis of its 
contents, was that it would be more valuable in 
agriculture than in horticulture, for that it was 
probable that it would diminish the size of the 
flower, but that it would certainly increase the 
produce of seed. I consider the above experiment 
with sweet-corn alone as considerably fortifying 
these views, and I will mention but one other of 
my numerous experiments; it is purely a horti¬ 
cultural one, but it further supports the same the¬ 
ory, which is very important to agriculture. 
In February, 1842, I repotted two plants, an old 
woody one, and a young cutting of heliotrope, 
which were in soil entirely exhausted, and in 
which they had been about 12 months. The ex¬ 
haustion of the soil was proved by the leaves turn¬ 
ing yellow and dropping off as fast as they appear¬ 
ed, as well as by the attenuated appearance of the 
shoots. On repotting, I merely added a teaspoon¬ 
ful of guano to the same soil, and replaced the 
plants in the same pots. In three months they 
had both shot out most luxuriant branches, with 
many clusters of flowers; and on the older and 
more woody plant, each cluster produced a good 
crop of seed, which this plant seldom produces, 
even under good common cultivation. This seed 
and luxuriance may therefore be fairly attributed 
to the guano. In order to pursue this subject to 
its farthest limits, I considered it valuable to dis¬ 
cover whether any of the ingredients, discovered 
by chemical analysis of this manure, had found 
their way permanently into the seed of the sweet- 
corn, with a view of ascertaining its importance in 
cultivation as an improver of the food either for 
cattle or man. I therefore forwarded a portion of 
the seed grown with guano to Mr. A. A. Hayes of 
Roxbury, to whose valuable discoveries and re¬ 
searches on this subject I have before alluded, and 
likewise to Dr. C. T. Jackson, who has also inter¬ 
ested himself much in these matters. 
Dr. Jackson I have not yet heard from, but the 
result of Mr. Hayes’s experiments on the corn I 
transmitted to him, is, that the phosphates in the 
guanoed corn, are to those in the corn without 
guano, as 6 to 4; in other words, the guanoed 
corn contains 50 per cent, more phosphates than 
the other. Now according to the most recent 
physiological discoveries, it is agreed that without 
the phosphates, neither flesh nor blood can be 
formed, and therefore, that the value of food for 
cattle and man, is dependant on the quantity of 
phosphates it contains. 
The facts may therefore be stated as follows : 
In a poor soil, with guano at the expense of about 
$3 per acre, a crop of Indian corn may be raised 
at least double in quantity to that raised on well- 
manured land; and this double quantity will con¬ 
tain 50 per cent, more of those ingredients, (phos¬ 
phates,) which are absolutely necessary to the 
formation of flesh and blood, than the other. 
I myself have repeated Mr. Hayes’s experiments 
with this corn, although I have not been able to 
separate the ingredients in the seed, so as to make 
a delicate and certain comparison with those of 
seeds grown without guano. Yet, according to 
the judgment of my eye, there is certainly an in¬ 
crease in the phosphates of the seed with guano. 
If this fact can be fairly once ascertained with one 
ingredient, it may be fairly supposed to be the 
case with others; and when the researches affect¬ 
ing agriculture, now being pursued by numerous 
able men of science, shall have attained a greater 
degree of precision and perfection, the importance 
of a knowledge of the. ingredients contained in the 
various foods of cattle and man, will become quite 
manifest. 
One other consideration has suggested itself to 
me as worthy of notice. In cultivation, the choice 
of fine seeds has always been deemed of first-rate 
consequence. If the seed of this first year’s sow¬ 
ing with guano has really acquired any more val¬ 
uable properties than that cultivated without, it is 
at least probable, from what we already know 
practically of the laws of vegetation, that these 
properties may be increased with another year’s 
similar treatment; I have therefore preserved 
some of this guanoed corn as seed for the succeed¬ 
ing year, when it will be again tried with the same 
manure. 
It is much to be regretted that an import duty 
of 20 per cent, ad valorem is levied on guano. 
This has just been paid on a small quantity im¬ 
ported into Boston, a good portion of which has, 
by the liberality of Capt. John Percival of the U 
S. Navy, been distributed among the members of 
the Massachusetts Horticultural Society; no doubt, 
however, that on proper representation being made 
at Washington, an article of so much importance 
to agriculture, will be admitted free. 
I will merely add to these statements, that the 
quantity of guano I consider desirable for each hill 
of corn of 5 seeds, is less than one ounce to be given 
in two applications. One quarter on sowing must 
be well mixed with the soil, and three quarters 
stirred well into the hill when the plant is about 
a foot high, always endeavoring to effect this lat¬ 
ter operation just previous to rain. This would 
give about 70 ibs. to the acre, supposing it to con- 
lain 1,100 hills at six feet apart. The price in 
England, is £10 to £12, or $50 to $60 per ton 
of 2,240 lbs.; hence the quantity to the acre would 
cost somewhat less than two dollars and no other 
manure is necessary. In England it has been ap¬ 
plied at the rate of 250 to 500 lbs. to the acre, or 
more than six times the quantity by the above 
calculation; but there it is scattered broadcast as 
the seed is sown, and of course the quantity used 
must be much greater, as all the ground is cover¬ 
ed. In the method I propose it is applied as it 
were simply to each plant. In England nothing 
is cultivated in hills, it is either broad-cast or in 
drills. 
There is unquestionably much still to learn on 
this subject: I am sure I do not pretend to have 
more than raised the skin of the scientific part of 
it; but of the great value of guano on poor and 
sandy soils under proper application, there can not 
exist a doubt. 
A remark has been made by some even of high 
authority in these matters, to the effect that hav¬ 
ing stimulated vegetation highly by these power¬ 
ful manures, should the application not be contin¬ 
ued, the soil would become exhausted and bar- 
j ren. Now is this not true of any manure, of 
