201 
GUANO, IN CONNECTION WITH FLORICULTURE. 
It might appear irrelevant to introduce the subject of Guano — the most poten- 
ial of all the so-called artificial manures of agriculture — in a work exclusively 
I'evoted to ornamental gardening ; but as we hope shortly to make it evident that 
his wonderful substance contains all the elements of vegetable nutriment, and as, 
,lso, we find that gardeners and florists begin to bend their attention to it, we 
lope that farther apology will not be needed for our present attempt. 
Little more will be required than a faithful detail of the constituents of this 
ubstance to prove, beyond a doubt, that it must possess a power and energy 
xceeding those of common manures ; a fact which also points out the necessity 
f employing the utmost caution in its use. 
Analyses of various samples have been effected, and the results printed, since 
804, when MM. de Fourcroy and Yauquelin examined the specimen introduced 
ly Baron Von Humboldt ; but it has been found that they all differ. At length, 
a 1843, Dr. Ure undertook an elaborate series of experiments, which appear to 
lave demonstrated that the only species to be relied upon for perfection of quality 
ire those of Peru and Bolivia. Assiduous researches have confirmed, to our own 
adgment, not only the general accuracy of the Doctor’s analyses, but tlie com- 
»arative worthlessness of samples obtained from other places ; therefore, we shall 
t once proceed to enumerate the chemical constituents of what we are assured are 
enuine samples of the Guano of Peru, undisturbed by that slow but progressive 
[ecomposition which inevitably results from exposure to air, moisture, and light. 
True Guano is of a palish drab-brown, tinted with a faint shade of red. It 
3 heavier than water, bulk for bulk, and, to speak more correctly, its comparative 
pecific gravity — water being 1.0— is about 1.70, little more or less. Some 
pecimens are interspersed with granular, whitish particles, which are evidently 
oncretions of certain neutral salts ; and this circumstance leads to the first essential 
emark, namely, that the components of Guano can be arranged under two distinct 
eads : the soluble^ or those which can readily be abstracted by pure water ; and 
;he insoluhle — that is, the substances which resist the solvent power of water, 
varm or cold. 
Guanos^ in the condition in which they are imported, contain more^ or less 
i^ater ; by drying at a heat not greater than that of boiling water, some samples 
Dse eight or nine, others from fourteen to eighteen per cent. ; the latter may be 
aid to be damp, a state which is, at the least, suspicious ; for if it have not 
jiduced chemical action, it at least implies the presence of common salt in excess, 
he loss by heat being ascertained must be allowed for, in process I, which 
onsists of subjecting from one to two hundred grains (for the sake of a “ per- 
entage ’ calculation) previously triturated in a wedgwood mortar, to the action 
VOL. XII. — NO. CXLI. 
D D 
