1849. 
THE CULTIVATOR. 
239 
ing a full compensation for his exertion, has a stronger 
and more powerful stimulant to activity than it is pos¬ 
sible to present to the slave. Hence, the latter is 
characterized by his lethargic movements, and indolent 
babits,—evincing a total disregard for the interests of 
his master, and I imagine is, in some cases, a source 
of expense, rather than profit. And there can be no 
doubt that the intelligent and educated laborer is far 
superior to the ignorant, and much cheaper, even at a 
greater salary. 
The expeiience of all those who have employed la¬ 
borers of both grades, I am confident, will speak in af¬ 
firmation of this opinion. But the most judicious man¬ 
ner in which the gentleman in question can substitute 
free, intelligent workmen, for his slaves, is a matter 
that cannot be decided without the most serious and 
thorough reflection. Whether he had better attempt 
to transform them into free laborers, or dispose of them 
either by selling them to southern planters, or giving 
them their freedom, and introduce free white labor 
from the north, is perhaps difficult to determine. I am 
satisfied that the adoption of either of these measures 
would be conducive to his interests. I would advise 
him to make some experiments, and give the results to 
his southern brethren, many of whom are similarly sit¬ 
uated, and would be grateful at their reception. 
I am of the opinion, however, that he will meet with 
more satisfactory success by disposing of his slaves as 
he best can, and bring free white laborers from the 
north. I doubt not, that he would hesitate selling them 
to the planters at the south; stilL I consider it prefera¬ 
ble to the course he is at present pursuing. If he be 
an individual of fortune, and would not suffer any in¬ 
convenience from the loss of his slaves, I scarcely need 
remark that the purer feelings of his heart would at 
once, dictate him to free them, when they are of a pro¬ 
per age. 
Let this be as it may, at any rate dispose of them. 
The number of free laborers required to till a farm 
of his description,, in a manner decidedly superior to 
that at present, and with far more lucrative results, 
would not exceed twelve. 
The foreman should be an individual of intelligence 
and education, and would demand a salary of $350 per 
year. The others, $125 each, most of whom might be 
sons of the Emerald Isle. This would make his annual 
expenses for labor on the farm $1725, which is no in¬ 
considerable item, and may at first appear rather start¬ 
ling. But if we take the interest of the money invest¬ 
ed in slaves, it will reduce this somewhat. He says 
there are some 60 or 70 around him, most of whom are 
slaves. Now, allowing that 56 are slaves, and suppo¬ 
sing their average value to be $250, (I am unused to 
such estimations, therefore may be greatly in error, but 
think this low enough,) he will have $14,000 invested 
in slaves, the interest of which, at 6 per cent., would 
be $840. 
Besides this, the number he will have to support will 
be reduced from 60 or 70 to 20 or 30, therefore the 
board of 40 will be saved, as well as the clothing of 
all, excepting his own family. The 40, at 35 cents 
per week for board, would cost $728 per year; and it 
is probable that the clothing averages $4 a-piece the 
year, which for the 56 would be $224. 
Adding these items together, we find that his slaves 
cost him $1792 a year, which sum exceeds the enor¬ 
mous amount that free labor would cost, by $67. If 
the estimates were more accurately made, doubtless the 
difference would be far greater in favor of free labor. 
If this be the result, it might be asked, how would the 
gentleman’s condition be materially improved? I an¬ 
swer ; the number of attendants around him would be 
vastly diminished, and his “ care and vexation” pro¬ 
portionally reduced. But besides this, he would with 
his free labor, adopt a new and improved system of ag¬ 
riculture, by which means the produce of his farm, 
would be doubled and tripled; and the fields that are 
already waning under that runious system of culture 
that will eventually, prepare them for augmenting the 
list of “ Virginia worn-out lands ” will be rescued and 
restored to their pristine fertility, by that more recent 
method of tillage, that causes even the granite hills of 
New England to smile with luxuriant verdure. 
In regard to the question whether grazing stock for 
market or cheese-making is more profitable, I would 
say that it depends entirely upon the situation and cir¬ 
cumstances. I do not recommend that the whole ener¬ 
gies of any farm, (unless it be a very peculiar one,) be 
devoted exclusively to the production of any one arti¬ 
cle; for not unfrequently, one branch of husbandry 
meets with reverses when others are prosperous. 
Therefore, it might not be improper for him to devote 
a portion of his farm to the grazing of stock for mar¬ 
ket, and another to the dairy. A good dairyman could 
be obtained for $300 per year. The necessary fixtures 
for cheese-making, could be erected for a sum varying 
from $250 to $800, depending entirely upon their extent 
and economical construction. 
Hoping that the gentleman will conclude to deviate 
from the time-beaten track of his ancestors, and free 
himself from the thraldom of slavery, which is twofold 
more injurious to the master than the slave, I cordially 
tender him my most sincere wishes for his success. P. 
Germantown , Pa. 
Mineral Cements.* 
Roman Cement. —It is a remarkable fact, in the his¬ 
tory of hydraulic mortars, which originates, as we have 
seen, with the Puzzolana and Trassf employed by the 
Romans, that the more the knowledge of their uses has 
been spread, the more substances have been discovered, 
which either act as hydraulic mortars themselves, or 
can be mixed as cemen's in the preparation of artificial 
mortar; so that what appeared originally a privilege 
accorded to a few favored spots only, can now be ob¬ 
tained almost everywhere. A strong inducement to 
study the nature and modes of occurrence of hydraulic 
lime, was created by the patent granted to Parker and 
Wyatt, in London, in the year 1796, for wdiat they 
termed “ Roman cement.” The materials, employed in 
the manufacture of this cement, are the nodules, of an 
ovoidal or globular form, 'which are found in the Lon¬ 
don clay, and known by the name of Septaria. They 
are not confined to the banks of the Thames, but are 
also found on on the isles of-^Sheppey and Wight, as 
well as on the coasts of Kent, Yorkshire and Somerset¬ 
shire. The composition of these nodules has already 
been given. They are calcined in perpetual lime-kilns 
with coal, in which a very moderate and well-regulated 
heat is carefully preserved. After calcination, the stones 
are ground under heavy edge-stones to a very fine pow¬ 
der, which is sifted and then packed in casks for sale. 
In the year X of the French Republic, Lesage point¬ 
ed out the existence of similar cement stones on the 
coast of France, near Boulogne, and Drapier proved 
their identity with the English, by chemical analysis. 
Roman cement is one of the most powerful hydrau¬ 
lic mortars, and is exceedingly valuable, not only on ac¬ 
count of the rapidity with which it hardens, and this is 
effected in a very few minutes, but because 'when hard¬ 
ened in considerable masses, it is not liable to crack. 
Since that time, similar calcareous marls have been 
found in numerous places, wherever pains have been ta¬ 
ken to look for them, and have been used for similar 
* From the second volume of Johnson’s edition, of Knapp's 
Chemical Technology. 
t Puzzoiana and Trass, are porous volcanic, or pumice stones. 
Eds. 
