220 
July 
THE CULTIVATOR. 
favor of allowing timothy to come nearer to maturity 
than most other kinds of grass, we would cut it for hay 
before much of its seed is ripened. 
The stems of timothy, where the growth is rank, are 
generally stiff and coarse, and the hay is frequently too 
hard and wiry to be greatly relished by cattle. To ob¬ 
viate this objection, it is well to give the hay a good 
sweating in cock. Soon after the grass is cut, or when 
it is fairly wilted, and the external moisture dried off, 
put it into cocks which will make from fifty to sixty 
pounds, (dry hay .) and let it remain in that situation 
for twenty-four to forty-eight hours. Then shake the 
hay out lightly, in a drying day, and it will be found 
much more soft and more agreeable to stock than if 
made in any other way. Time is also gained in the 
making in this way,—the hay drying much more rapid¬ 
ly after it has been sweated. Where it is intended to be 
pressed and baled, or exported, the practice of drying it 
in swath may do, provided the grass is not cut till it has 
become quite ripe 5 but the hay will be harsh and not as 
good, especially for sheep and cattle, as that made in 
the mode above described. 
FIXING* AMMONIA. 
Messrs. Editors —Your correspondent, T. H., of 
Colchester, Canada West, and yourselves, invite re¬ 
marks upon the above subject, in your last number. If 
you please, you may insert the following from a “ chemi¬ 
cal friend” who takes and reads the “ Cultivator,” al¬ 
though not a practical farmer. 
First, as to facts in the case. Gypsum, or sulphate 
of lime, is not a super-salt, or rather, there is no super¬ 
sulphate of lime, as supposed by T. H. Gypsum is 
composed of one equivalent of sulphuric acid, and one of 
lime, and two equivalents of water, (i. e.) the common 
gypsum used for agricultural purposes. Gypsum and 
carbonate of ammonia when brought in contact, at com¬ 
mon temperatures, will mutually decompose each other, 
and the resulting compounds will be sulphate of ammo¬ 
nia and carbonate of lime. The ammonia in rain wa¬ 
ter is in the form of a carbonate , and gypsum “fixes” 
the ammonia by the two compounds mutually decompo¬ 
sing each other, and converting the ammonia into a sul¬ 
phate, which is a, fixed salt, thus rendering it useful to 
vegetation. The difficulty with T. H. seems to be that 
he does not reconcile this with his table of affinities. 
The difficulty in the matter seems to lead T. H. to 
doubt the facts. Now, rio absolute reliance can be 
placed upon tables of affinities, in all cases, as was once 
supposed by Geoffrov and others. There are so many 
disturbing extraneous causes, that the exceptions in many 
cases would form the general rule. Among these dis¬ 
turbing causes, we may mention heat, light, electricity, 
and cohesion or density—all tending to disturb our ta¬ 
bles of affinities, so that should we place too much re¬ 
liance upon them, they might lead us to contradictory 
and erroneous conclusions. “ Sulphuric acid has a strong¬ 
er affinity for lime,” says T. H., “ than for ammonia.” 
It is true that the affinit}' - between the elements of gyp¬ 
sum is greater than between the elements of sulphate 
of ammonia; but it is not true, as T. II. says is ‘'evi¬ 
dent to his mind,” that carbonate of lime and sulphate. 
of ammonia will, when mixed together, mutually de¬ 
compose each other. No chemical action takes place 
under the circumstances supposed. An experiment that 
will prove two things, may be tried in the following 
manner: Add to two quarts of pure rain water, in a 
chinaware dish, about a tea spoonful of sulphuric acid, 
then evaporate nearly to dryness, then add a little pul¬ 
verized lime, and you will readily perceive the peculiar 
smell of ammonia. Now this proves, that there is am¬ 
monia in rain water, and that lime will decompose the 
sulphate of ammonia, forming sulphate of lime; but 
Xnind, there is no carbonic acid present. That escaped 
in the form of a gas when the sulphuric acid was added 
to the rain water. If carbonic acid had been present, 
it would have prevented the chemical change. Now, 
neither carbonic acid or ammonia alone , will decompose 
gypsum or sulphate of lime; but when the two are to¬ 
gether, which is always the case in rain water, sta¬ 
bles, &c., where ammonia is sensibly present, from the 
decomposition of animal matters, a mutual decomposi¬ 
tion takes place. The ‘ ‘ apparent discrepancy,” if any, 
may be explained in the following manner, by what, in 
the books,is called “ double elective affinity.” But I will 
explain it, I think, so that all your readers will readily 
understand it. Let the force or affinity by which the 
elements of gypsum (sulphuric acid and lime,) are held 
together, be called “ quiescent ” affinity, and (for illus¬ 
tration,) be represented by 20 . Again. Let the force 
or “quiescent” affinity between the elements of carbon¬ 
ate of ammonia be represented by 5. Now bring the 
two compounds together, and a new set of affinities is 
brought into action, viz: between the sulphuric acid and 
ammonia, and between the carbonic acid and lime. 
These new affinities are called “divellant,” and are 
greater than the “quiescent” affinities, in the case in 
question. We will suppose, for illustration, the affinity 
between the sulphuric acid and ammonia, to be 15; and 
between carbonic acid and lime, 15 also; the result 
would be as follows: 
Quiescent Affinities. 
Sulphate of lime,. 20 ) ... _ r 
Carbonate of ammonia, 5 ) e I ua in S 
Divellant Affinities. 
Sulphate of ammonia, 15 
Carbonate of lime, .. 15 
equalling 30. 
Now you perceive that the sum of the “divellant” 
affinities is greater than the sum of the “ quiescent ” 
affinities; and hence the change. But you take carbonic 
acid out of the question, which T. H. does not take into 
aceount, and you abstract a force or power in the sup¬ 
posed case, equal to 15, which in the case in question ex¬ 
ists between the carbonic acid and lime, tending directly 
to separate the lime from the sulphuric acid. Thus, you 
perceive, that the table of affinities of T. H. is no guide 
any farther than “ single elective affinity ” is concerned, 
which takes place in the case in question, when carbo- 
nic acid is absent. I think this will be sufficient to ex¬ 
plain the modus operandi in the change in question. 
Now, Messrs. Editors, the fact that gypsum will fix 
the ammonia that descends with the gentle dew and rain 
from heaven, and thereby render greater facilities for 
vegetation to acquire the indispensable principle nitro¬ 
gen, is a wonderful and most valuable discovery in these 
days of progress; far more useful, perhaps, to the hu¬ 
man family, than the fabled waters of Lethe, or its more 
modern reality , which sooths the system into quiet and 
repose, and renders it insensible to the surgeon’s knife. 
It is no doubt a great boon to mankind to be relieved 
from the consciousness of pain while undergoing the se¬ 
vere ordeal of surgical operations. Yet the pains and 
horrors of starvation, which can neither be removed or 
alleviated by any fabled or real Letheon, but demand 
