Fertilizers 
G. M. Wakelin 
Mr. President, Ladies and Gentlemen : 
It would be a difficult matter to present 
' to the members of this society a paper 
on fertilizers, giving them anything par¬ 
ticularly new or original. The great ma¬ 
jority of the members of some years’ 
standing are well informed on the sub¬ 
ject, and it would be presumptuous on my 
part to suppose that I could add to their 
store of knowledge. However, we have 
not all thrashed and rethrashed this sub¬ 
ject, so it may be that a little review of 
one of three important elements of plant 
food will prove interesting. 
THE SUBJECT IS PHOSPHORUS 
This is from the Greek word Phosphor, 
the Latin equivalent is -Lucifer, both 
meaning “light bearing,” and were the 
names given the morning star, usually 
Venus, when it precedes the sun. The ele¬ 
ment phosphorus was then so named be¬ 
cause it glowed. 
It is one of the simple elements, chem¬ 
ical symbol P., not a compound, and in a 
pure state is a non-metallic soft solid. 
Phosphorus cannot be kept in this form 
except under oil, for on exposure to the 
air at ordinary temperature it undergoes a 
slow glowing combustion, and oxidizes to 
the compound called phosphorus pentoxide 
P2O5. This again will take on water and 
become phosphoric acid H3P2O4. Phos¬ 
phorus is not found in nature except as 
the salt of phosphoric acid and some basic 
element such as calcium. This is its most 
abundant form, known to all as natural 
phosphate, soft rock and pebble; and 
again found the world over as the min¬ 
eral apatite, and again in marl. This is a 
combination of phosphate of calcium and 
fluorin or chlorin. By some this is sup¬ 
posed to be the one original source of all 
the phos. found in nature. Phosphate of 
calcium again comprises the greatest part 
of all bones of fish, birds and animals, 
and the element P. itself in combination 
with other elements constitutes the sub¬ 
stances called proteins, found in the cell 
structure of every living thing and its 
product. 
By common usage the P. in fertilizers 
is called phosphoric acid, but figured as 
phosphorus pentoxide. Forty-four per 
cent (App.) of “Phos Acid” (P2O5), so 
called, is phosphorus, though of course we 
understand that this P. exists as Phos- . 
phate of Ca. It would probably be better 
usage and more instructive to figure on 
fertilizer elements as N. instead of Am., 
potassium instead of potash, and phospho¬ 
rus instead of phos acid. Roughly speak¬ 
ing— 
N is 82 per cent of ammonia (NH3) 
K is 83 per cent of potash (K2O) 
P is 44 per cent of “Phos Acid” (P2O5) 
And P. is 20 per cent tricalcium phos- 
62 
