THE RURAb NEW-YORKER 
June 8, 
use is rapidly expanding in them. A simple and ef¬ 
fective way to begin is by establishing cooperative 
purchase societies through which farmers can buy 
a few of the more commonly used goods. The suc¬ 
cess of these societies will soon lead to the adoption 
of other forms of agricultural cooperation and its 
general adoption means a revolution of American 
agriculture. H. C. price. 
Halle a. Sale, Germany. 
MAGNESIAN vs. PURE LIMESTONE. 
Is the Former Objectionable ? 
Last January yon published an interesting article on 
lime vs. stone, by Franklin Noble, in which he makes some 
statements which are, 1 believe, intended to be a slur or re¬ 
flection upon magnesian limestone. For example, he says : 
“Fresh-water shell marl is found in large deposits practi¬ 
cally pure lime carbonate, because of the method of its 
formation, quite different from salt-water shell marl,” and 
further on : “Consequently judged by results a ton of non- 
magnesian, finely powdered carbonate of lime, such as 
found in fresh-water shell marl and some ground lime¬ 
stones is worth more to the farmer than a ton of burnt 
lime.” Elsewhere in your paper, I believe, I have seen 
similar indications of a real belief that limestone contain¬ 
ing magnesia, and sold as lime, is substantially adulter¬ 
ated, or at least inferior. Inasmuch as nearly all lime¬ 
stones contain some magnesia, and many X’egions are prac¬ 
tically limited to magnesian limestone, though having 
plenty of that, it is a serious inquiry whether these in¬ 
timations or this supposition is justified. It may be an¬ 
swered that lime is wanted not so much because of its 
immediate contribution to the plants as because of its 
chemical action on the soil. To this I reply that the 
action of magnesia is in nearly all respects identical with 
that of lime. In fact magnesia is so closely allied with 
lime chemically, its reactions being nearly all the same, 
that to separate it from lime, chemists have to resort to 
a double compound with ammonia, these double compounds 
of ammonia and lime being less soluble than those of 
ammonia and magnesia. Magnesia and lime are almost 
equally common constituents of the earth’s crust, and 
constantly found together in natural processes and in 
soils. In Geology of Wisconsin, Vol. 2, page 107, Pro¬ 
fessor T. C. Chamberlain calls attention to the magnesian 
character of certain Wisconsin soils: “This, I believe, in 
the future unfolding of agricultural science, will be found 
to be a very important fact. Magnesia has been a much 
abused substance. ... It may be asked whether the 
well known superiority of Wisconsin wheat is not due to 
the magnesian element of her soils.” 
Professor Chamberlain’s words are not to be lightly re¬ 
garded. I think this matter should be thoroughly ven¬ 
tilated in your columns. Doubtless magnesian limes will 
be found better suited for some crops than others, and for 
some soils than others, regard being had to the relatively 
greater solubility of magnesian humus compounds ; hut let 
us keep constantly in mind one thing—that so far as 
opening the pores, releasing potash salts, neutralizing 
aciditv. etc., etc., are concerned, magnesia and lime are 
substantially tweedledum and tweedledee. o. c. 
Wisconsin. 
Magnesia as Necessary as Lime. 
Magnesia is as necessary to plants as lime, so far 
as mere plant food is concerned. In neutralizing soil 
acidity magnesia is quite as effective as lime. Our 
experiments show that it is easier to use magnesia to 
excess than lime, although cither substance, like any 
other good thing, if used in too large quantity, will 
produce an injurious effect instead of a benefit. Fur¬ 
ther experiments seem to indicate that it is important 
to maintain such a proportion between the magnesia 
and lime that the lime will always be in considerable 
excess of the magnesia. Some soils seem to show 
more magnesia than lime. On such soils it would 
seem probable that caution should be exercised in 
using lime containing a large percentage of magnesia, 
but where there is no such excess of magnesia in 
the soil a lime containing up to 25 or 30 per cent mag¬ 
nesia is probably not objectionable, but often better 
than an entirely pure calcium lime would be. In our 
experiments we have used either the magnesian or 
calcium limes, as is most convenient, and thus far 
have discovered no ill effect from the magnesian lime 
when used in the quantities we use; namely, the equiv¬ 
alent of one ton per acre of caustic lime, or two tons 
per acre of ground limestone. It is probable that in 
the case of the raw stone there would seldom, if 
ever, be any injurious effect from the use of a mag¬ 
nesian lime. chas. e. thorne. 
Ohio Station. 
Functions are Similar. 
So far as we know the functions of magnesia are 
similar to those of lime. It is only when applied in 
large quantities in the absence of a proper propor¬ 
tion of lime that ground is given for objection to its 
use. Magnesia carbonates less rapidly, and in large 
quantities may keep tbe soil in too alkaline a condi¬ 
tion. Moderate applications of the magnesian limes 
of Pennsylvania can be made without fegr when lim¬ 
ing is indicated as desirable. M. s. mcdowell. 
Pennsylvania Station. 
Magnesian Limes are Effective. 
So far as I know, there are no experiments on rec¬ 
ord in this country on the subject of tbe comparative 
effects of magnesian limes and pure limes. We have 
started a modest experiment on the subject, but it will 
be some years before we get anything definite from it. 
Stockhardt, in his classic field sermons, stated long 
ago that magnesian limestone, when burned, was 
highly valued by the German farmers, and, accord¬ 
ing to general experience, worked more effectively 
and continuously than the pure limes. He had used 
as high as about 1,500 pounds to the acre, with no 
bad effect. There is further testimony from France 
and England to the same effect. 
Meyer’s experiments show that in a soil poor in 
lime an addition of carbonate or citrate of magnesia 
produced as good results in crop as an addition of 
carbonate of lime. On certain legumes he found 
that magnesia in form of carbonate on a sandy soil 
Very poor in lime produced as much increase as lime 
alone, but that the two together did better than either 
separate. He got a better result with carbonate of 
lime alone in an experiment with mustard. Pound 
for pound, of course, magnesia will neutralize a 
greater amount of acidity than lime. So far, there¬ 
fore, as we have any information on the matter, it 
seems to me we are justified in the opinion that 
magnesian limes are as effective as pure limes on 
agricultural soils. e. h. jenkins. 
Connecticut Station. 
Magnesian Limestone a Little Ahead. 
In our comparative experiments with Alfalfa we 
find that magnesian limestone is just a trifle ahead 
of common limestone in efficiency, though the dif¬ 
ference is not enough to be of any practical account. 
In some experiments, however, the magnesian lime¬ 
stone seems to have worked considerably better; in 
others the pure limestone. Apparently there are 
some soils in some States where a little magnesia is 
very helpful perhaps as plant food. 
If magnesian limestone has been burned and slaked 
and applied to the land it is possible that the carbon¬ 
ate of magnesia eventually formed is more soluble 
than the carbonate of lime, in which case if large 
quantities of it were used it might be objectionable. 
However, when the natural ground magnesian lime¬ 
stone is applied it is doubtful if the carbonate of mag¬ 
nesia would be as soluble as the carbonate of lime. 
At least I can quote Professor Hilgard of California 
THE “CHAMPION” STONE PENCE. Fig. 225. 
as authority for the greater solubility of carbonate of 
lime than of carbonate of magnesia as the carbonate 
of magnesia ordinarily exists in nature. Of course 
the physical character of the compound would be dif¬ 
ferent where it is formed naturally than it would 
where it had been slaked and it was formed quickly 
within the soil. It is for this reason that magnesia 
may accumulate in the soil more than lime and hence 
on a soil which already contains too much magnesia 
it may after a time accumulate in quantities which 
would be so out of proportion to the lime as to be 
injurious to certain plants. This, however, could be 
overcome by alternating the applications of magnesian 
limestone with applications of pure limestone, rather 
than to use the magnesian limestone continuously. So 
far as sweetening the soil is concerned it does have 
the same effect, though if it is rather less soluble 
than carbonate of lime the effect might be slightly 
less at the outset depending upon the physical char¬ 
acter of the special material used. The chemically 
precipitated carbonate of magnesia is, however, more 
soluble in carbonated water than the carbonate of 
lime compared under the same conditions. 
Rhode Island Station. H. j. wheeler. 
Magnesian Limestone for Illinois. 
From all of the information I have been able to 
secure I am of the opinion that magnesian limestone 
is better for use in soil improvement as a general 
rule than the high-calcium limestone. We are using 
in Illinois very considerable amounts of magnesian 
limestone which consists of nearly pure dolomite, a 
double carbonate of calcium and magnesium. So far 
as I know the magnesian limestones of the United 
States consist either of dolomite or of a mixture of 
dolomite and ordinary limestone; that is, a mixture 
of the double carbonate of calcium and magnesium, 
together with more or less ordinary calcium carbon¬ 
ate. I do not know of any deposits of limestone in 
the United States carrying more magnesium car¬ 
bonate than would be contained in dolomite. While 
burned dolomitic limestone has a bad reputation, as 
you will see from the quotations on page 160 of my 
text book on “Soil Fertility and Permanent Agricul¬ 
ture,” the unburned stone seems never to have given 
results to create any prejudice against its use. 
On my own Illinois farm I have used several car¬ 
loads of dolomite and so far as I have been able to 
see it has given at least as good results as high- 
calcium limestone. I know where as much as 20 tons 
per acre of dolomitic limestone has been applied with 
only beneficial results. Magnesium is an essential ele¬ 
ment of plant food as well as calcium, and the mag¬ 
nesium carbonate contained in dolomite is even more 
effective, pound for pound, for correcting soil acidity 
than is the calcium carbonate. It is conceivable, of 
course, that an application of dolomitic limestone to 
a soil which already contains such an amount of mag¬ 
nesium as to approach the point of injury would 
prove deterimental, but soils of this character are 
surely exceedingly rare, and I do not know that they 
exist at all where used for agricultural purposes. At 
the same price per ton I prefer to use magnesian lime¬ 
stone (dolomite) on my own farm. 
Illinois Experiment Station. cyril g. hopkins. 
ANOTHER STONE FENCE. 
Lest we lose interest in the rivalry for “the 
largest stone fence,” I submit a photograph of 
a fence that has all rivals beaten to a standstill that 
have so far come forward. This, shown in Fig. 255, 
is situated in Northern New York in a “rocky” sec¬ 
tion. Its dimensions are: Length, 650 feet; width at 
base, 21 feet, at top, 15 feet; height, five feet, and 
contains 58,500 cubic feet of stone; or 1,840 wagon¬ 
loads ; or 460 cords; or 92 carloads; or two train 
loads of 46 cars each. A faint idea of the labor repre¬ 
sented in this monument to the industry of early set¬ 
tlers may be gained when we reflect that at 10 loads 
per day it took one man with a team 184 days to 
gather and deliver the stone. In a letter to the writer 
from Mr. R. V. Rizer, Chief Clerk, U. S. Geological 
Survey concerning boulders, etc., as found throughout 
Northern and Central New York, Mr. Rizer writes: 
“They were originally derived from the parent ledges, 
largely granite, in Canada, having been plucked out 
by the moving ice where they were loosened by 
cracks and joints in the ledges. * * * If you go 
back to the various modes of formation of the dif¬ 
ferent kinds of rocks that are found in the parent 
ledges you will find that the conditions of their 
formation depend on this kind of rock. For instance, 
granite rocks were solidified from molten magmas by 
cooling; limestones are composed of calcareous sedi¬ 
ments originally deposited in seas. * * * Some 
of the fragments from the parent ledges got their 
roundness from weathering, others by abrasion by 
moving glacial ice, others by being washed and rolled 
along by streams or being worn by the waves of the 
beaches of ancient or modern lakes or seas.” 
C. F. BLEY. 
THE LONG ISLAND FARM COLLEGE. 
Your request for my opinion as to what the Long 
Island farmers most need from the new College of 
Agriculture, is at hand. Of course all students, 
whether from the farm or city, will need the scientific 
side of farming, the why of things. In addition it 
is very desirable that all should have considerable 
instruction along the mechanical side, the how of 
the operations. As a practical farmer there are 
several questions that apply to our conditions that I 
would like to see worked out. This is not a dairy 
country, and the question of the best way of keep¬ 
ing up our supply of humus is an important one. 
How much can we afford to pay for city stable ma¬ 
nure? Is it cheaper to skip a crop now and then 
in order to plow under a catch crop? 
The question of irrigation is going to be a great 
and important one in the future. We want to know 
if the thousands of acres of our light soil can be 
utilized profitably by irrigating, and in what way, and 
for what crops. It is probable that nearly all of our 
soils need lime. How much we need and the best 
way to use it so as not to make it impossible to raise 
potatoes without causing them to be scabby, what 
form of lime to use and various other questions along 
this line. With our different soil, climate and crops 
there are many insects and diseases that we could 
control, if we knew how, that do but little injury in 
the rest of the State. 
It would be desirable to find out the different kind 
of vegetables we could raise profitably, and the varie¬ 
ties that do best under our conditions. Methods of 
intensive culture under irrigation is a good field for 
investigation and experiment. Methods of packing 
and marketing are important and is something on 
which we need more information. There are many 
other problems that might be mentioned. Of course 
many of these are questions for the experiment sta¬ 
tion rather than the college, but practical demonstra¬ 
tion is many times as valuable as science and theory. 
Finally, no school of agriculture of the future is 
going to be complete without provision is made to 
instruct its students in the need of cooperation among 
the farmers. About every other class of people is 
organized to pull together, and unless the farmers 
learn to work together we will be the prey of them 
all. H. R. TALMAGE. 
