THE RURAL HIW-Y 6 RMER 
planting and one of our hens got at it and 
ate up every grain. I was bound not to be 
beaten so I caught that lien, cut open her crop, 
took out the corn and planted it. It all grew. 
As for the hen, she did well, laid an egg the 
following day and has reared a brood of chicks 
this spring and already weaned them. 
Richland Co., Ills. b. f. Kent. 
[R. N.-Y.—Seeds retain their vitality under 
very tryiug circumstances; with weed seeds 
this fact is often painfully evident. It often 
happens that after years of the most patient 
and careful battle against weeds the farmer is 
discouraged by a fresh crop from seeds which 
have lain dormant in the soil. Dr. Lindley 
tells of raspberry seeds buried for years in the 
stomach of a man. They were finally removed 
and planted and produced strong plants. The 
cutting of a hen’s crop is sometimes an act of 
mercy. Where the birds are “crop bound,” 
that is where a hard mass of undigested food 
gathers in the crop, it can be safely removed 
through an opening made through the skin. 
This opening must, of course, be sewed up and 
treated like any other wound.] 
I have had some favors from that “Seed 
Shop.” In 1871 I saw a monthly report of the 
Agricultural Department. I sent and got 
some seed which has been worth $50 to me. I 
had seeds about four times. They always 
grew, but were not always pure or true to 
name. Our public money is wasted in hun¬ 
dreds of ways. Out here a political job uses 
up the money spent at improving the mouth 
of the Columbia River, so that the saud is 
never kept back. r. l. j. 
Mishawka, Oregon. 
I have a small piece of rye near my barn¬ 
yard. It is now two inches high, while the 
grass in the pasture is not half long enough for 
a bite. I turn the cows into this piece about 
two hours a day, The way they eat and the 
way the milk comes couvinee rneitisgood 
business. When they get to the pasture t hey 
won’t bloat, tlionise] ves ns they have done in 
years past. This is as far as I have ever gone 
with soiling, but it pays well thus far. 
Bergen Co., N. J. c. T. v. 
Tjte cartoon on the first page of the Rural, 
for April 0 is as tip-top a Orange sermon as I 
have seen in many a day. It is a hard hit on 
Tom, Dick aud Harry of the plug-hut tribe. 
Sec. Ills. State Grange. thos. ready. 
Enrol koines. 
j 
HORSE POWER OF STEAM ENGINES. 
PROFESSOR R. C. CARPENTER. 
Meaning of “horse-power;' 1 ' horses and en¬ 
gines as motive powers; mode of ascertain¬ 
ing horse-power; steam expansion; nomi¬ 
nal and. actual horse-power; horse-power 
of an engine varies with the conditions; 
strength of horses; strength of a horse 
equals two-thirds a horse-power of an en¬ 
gine; variations in pouter of a horse; power 
of machines; absurd 'misrepresentations. 
The work done by a steam engine is usually 
expressed in units of work called “horse¬ 
power.” This term was invented by James 
Watt, who defined it ns the ability to lift 33,- 
000 pounds one foot each niinnte or a less num¬ 
ber of pounds an equivalent number of feet 
per minute. In obtaining this unit, the 
actual work of a large number of 
horses was measured, from which it was 
found that the work of the average horse, 
working ten hours per day, was equivalent 
to 22,000 pounds lifted one foot each minute. 
From this it is seen that the unit adopted for 
the steam engine is 50 per cent, greater than 
the work of the average horse. This I think is 
in accordance with experience where steam 
has been substituted for horses in driving the 
machinery, i have made many inquiries of 
some thrashers, receiving the inevitable answer 
that a ten-horse-power engine gave very 
much more power than ten horses. It is, no 
doubt, true that mauy have met with 
experiences very different from this, especially 
when engines nominally of two or three horse 
power have been substituted for the same 
number of horses. This probably cannot bo 
accounted for except in a general way; but, 
no doubt, it comes from the fact that either 
exceptionally strong horses bad been used, or 
that the engine did not develop its nominal 
horse-power. 
The nominal horse power of an engine is cal¬ 
culated by multiplying the average steam 
pressure acting on each square inch of the pis¬ 
ton, by its areu and by the space paased 
through in feet per minute and dividing that 
result by 83,000. This, of course, is somewhat 
greater than the power actually developed, as 
it makes no allowance for friction and other 
losses. As the engine becomes smaller these 
losses become a greater and greater proportion 
of the work of the engine. The average steam 
pressure acting on the piston is much less than 
the boiler pressure. This is due to two facts: 
first, the steam is expanded to a greater or 
less degree after it gets into the cylinder, and, 
second, there is more or less of pressure in 
conveying the steam from the boiler to the 
cylinder. 
In obtaining the nominal horse-power of 
small engines, manufacturers usually count 
on an average pressure of 40 pounds per square 
inch on the piston. To secure this pressure ou 
the piston a boiler pressure much higher will 
he needed, depending on the expansion of the 
steam after it reaches the cylinder and on the 
losses. When an engine is sold the manufac¬ 
turer should state clearly what steam pressure 
should lie carried in the boiler to develop the 
nominal horse-power. The governor which is 
furnished with the engine should be set so as 
to give the proper speed. The expansion of 
the steam in the cylinder is accomplished by 
closing the port that admits steam before the 
piston has finished its stroke. In large engines 
this port is sometimes closed as early as one- 
eighth of the stroke of the piston; but in small 
engines designed to run at high speed, it is 
closed much later. In very small engines live 
steam is usually made to follow the piston 
uearly through its stroke; in this way more 
power is developed from a smaller engine, al¬ 
though at a slightly greater expense for fuel. 
Figures 187 and 188 on the diagram will, 
77 #/ 
Fig. 187 and 188. 
no doubt, serve to make the foregoing state¬ 
ments clearer. Lot the horizontal line repre¬ 
sent the stroke of the piston, and suppose it, for 
convenience, divided into 12 parts. Through 
each one of these parts draw a vertical line, 
aud make its length proportional to the pres¬ 
sure acting on each square inch of the piston, 
when in that position. Join the ends of these 
pressure lines and the result will he a diagram 
like that, shown in Fig. 1 and Fig. 2, in both 
of which FG represents line of atmospheric 
or no pressure. The urea of these diagrams 
will represent the work done at each stroke of 
the piston. The diagram in Fig. 187 repre¬ 
sents the case wheu the steam is admitted only 
l'or one-third of the stroke of the piston; that 
at Fig. 188 is the case in which steam is ad¬ 
mitted for three-fourths the stroke. In each 
diagram the piston is at 1, moving toward 0 
when steam is first admitted, and the pressure 
is nothing. The pressure vises to AB, stopping 
the piston at O, aud starting it in the reverse 
direction. These pressure lines remain of the 
same length until the piston gets at B, at 
which time the steam port is closed ana the 
pressure falls at the successive positions of the 
piston as shown by the shortening of the lines 
between CD and E D. At C the port opens 
from the exhaust side and nliows the steam to 
escape so that the pressure falls to the line E 
D, which is that of the air in non-condensing 
engines, if there is no back pressure. The re¬ 
verse operation takes place on the other side 
of the piston, ami would bo represented by a 
diagram of similar form, but turned tlie other 
side to. 
The length of the line C D represents the 
pressure not used, and consequent loss. This 
is greater in Fig. 188 than in Fig. 187. In 
very large engines this loss is an important 
matter, and every means are taken to get, all 
the power possible out of steam. Any de¬ 
rangement of the valve motion affects very 
materially the form of these diagrams, and 
consequently the power of the engine. Some¬ 
times a certain amount of steam gets on the 
wrong side of the piston and opposes its 
motion, so as to decrease the power very ma 
terially. Now, the nominal horse power of 
an engine can be realized only when the en¬ 
gine is in perfect order and running without 
friction, ns has been shown by the foregoing 
explanation. The actual horse power should, 
however, be greater in case of an engine in 
good order than the same number of horses of 
average strength. Hy running the engine at 
higher sjieed than rated, or carrying a higher 
steam pressure, the actual horse power 
developed may be made to exceed the nominal 
horse power. 
From the fact that the power of an engine 
varies within such wide limits,aud depends on 
conditions which the maker can have no con¬ 
trol of, most, reputable makers will give no 
guarantee of the horse power of their engine 
unless they know every condition under which 
it is to be worked. They very much prefer to 
sell an engine of a specified size rather than of 
specified power. The nominal horse power of 
small steam engines is found very nearly by 
squaring half the diameter of the cylinder. 
Thus an engine with cylinder six inches in di¬ 
ameter, would usually be called a nine horse 
power engine, sometimes a 10 horse power. 
When the cylinder is seven inches in diameter 
we have a 12-horse power engine. When the 
cylinder is four inches in diameter, wo have a 
four horse power engine. This rule is a mere 
accident, and is true only for small engines 
with cylinders not exceeding eight inches in 
diameter. This is true simply because the 
speed of piston per minute for those engines is 
usually about 200 feet for assumed average 
pressure of 40 pounds, or 220 where the aver¬ 
age pressure is assumed to be 50 pounds per 
square inch of piston. With a mean average 
pressure ou the piston of 50 pounds per square 
inch, the following values of diameter of cy¬ 
linder aud speed of piston in feet per minute 
will be found: 
Nominal 
Horse Power. 
Diameter of Cy¬ 
linder In Inches. 
Piston Sneed In 
Feet per Mlnute. 
1 
2 
220 
2 
2% 
230 
8 
ahs 
220 
4 
4 
220 
6 
5 
210 
9 
fi 
210 
10 
8% 
220 
12 
7 
204 
The piston speed in feet per minute can 
always he readily figured when the length of 
the stroke and the number of revolutions per 
minute are known. The strength of any par¬ 
ticular horse is an uncertain amount, but the 
strength or power of an average horse may bo 
known within quite narrow limits. I have 
already mentioned the investigation of James 
Watt, who found that the strength of an aver¬ 
age liorso used iu pulling was 22,000 pounds 
raised one foot per minute, or two-thirds of 
the horse power of the steam engine. This is 
supposed to represent the strength of a strong 
and well-fed. horse that can be exerted stead¬ 
ily for ten hours each day. 
For shoi*ter periods of time much more 
strength can be exerted. Trantwein says that 
the strength is increased as the day’s work is 
shortened, aud a horse working but five hours 
per day can exert twice as much force per 
hour as one working ten hours per day. 
There is no question but this latter principle 
holds true to a certniu extent, and no doubt, 
in some cases may account for deficiency in 
power of an engine when compared with 
the power of horses. It is, no doubt, true that 
horses can do more work in some positions or 
when using certain sots of muscles than in 
other positions. Thus a man can do about 40 
per cent more work in a tread-mill when he 
uses the muscles of both arms and legs than 
when he uses his arms alone. 
Nystrom does not, however, find this to 
hold true with horses in a tread-mill. We 
have seen that the horse eau do work that is 
equal to two-thirds or 07 per cuut nearly of a 
horse-power by traction alone. 
Nystrom says in a tread-mill at a speed of 
three feet per second, a horse can exert 57 
per cent, of horse-power, and at a speed of 
nine feet per second, he can exert only 10 
per cent, of horse-power measured in pounds 
lifted feet per minute. 
It is frequently claimed by salesmen of 
machinery that by means of their machines 
more power is developed than is supplied to 
the machine. This may be made to look 
reasonable by the specious words of an agent, 
or even by watching the machine itself, when 
nothing definite is known of the power sup¬ 
plied. This doctrine is, in reality, more pre¬ 
posterous than that of perpetual motion, for 
it not only assumes that no power is required 
to run tlie machine, but that besides running 
the machine it actually does work in addi¬ 
tion. It is true that more work may usually 
be done with a machine thau without it, but 
that is because the power is applied to so much 
better advantage, as to more than compensate 
for any loss. 
SrlunlciiHurol. 
BETTER THAN THE NORWAY SPRUCE 
AND BALSAM FIR. 
the rural’s views pretty well supported 
BY THOSE WHO SHOULD KNOW. 
Notes from Robert Douglas ( Waukegan, 
Ills.), Stores d> Harrison (Dainesville, n.), 
Ellwanger <f Burry (Rochester, N. Jr.), 
Josiah Hoopes (Westchester, Da.), Chas. A. 
Dana (Long Island, N. Y.) Deter li. Mead. 
The Rural New-Yorkkk has been sharp¬ 
ly criticized for condemning the Norway 
Spruce and the Balsam Fir as evergreens for 
ornament. We have especially condemned 
the Balsam Fir, believing it to be a worthless 
tree. We are now able to present the follow¬ 
ing views from distinguished arboriculturists 
who have kimlly replied to our inquiries: 
FROM CHARLES A. DANA. 
“I would not plant a Norway Spruce at all, 
nor a Balsam Fir except in some place pecu¬ 
liarly suited to it. The White Pine is the best 
evergreen for this part of the country (Long 
Island, N. Y.). The Dougins Spruce promises 
well, but has not been tried sufficiently. The 
same is true of the Picea pungens. With 
proper treatment the Nordmann’s Fir, the 
Cilicican Fir, the Cnncolor Fir, and the Ceph- 
aioninn Fir are well worthy of preference. 
The Atlas Cedar is an admirable evergreen. 
The Retmlspora family of Japan should uot 
be overlooked. The American Hemlock and 
the Japanese Hemlock arc both superior in 
beauty to the Norway Spruce. Among pines 
proper,the Red Pine (Pinus resinosa), the White 
Pine (P. Strobus), the Cembra or Stone Pine 
and the Ayacnhuite are deserving of great 
attention." 
[R. N.-Y,—Picea pungens is the Blue Spruce 
of Colorado (Abies Engelmannii and Abies 
Menziesii), so often praised by the R. N.-Y. 
The Atlas Cedar is Cedrus Atlantica. The 
Japan Hemlock is Abies Tsuga. The Pinus 
Ayacahuitu seems to thrive well among Mr. 
Dana’s almost unequaled collection of conifers 
in his island of “Dosoris” on Long Island 
Sound. But it fails at the Rural Grounds 
and is not hardy in Rochester.—E ds.] 
FROM ROBERT DOUGLAS. 
The Colorado Blue Spruce and the Douglas 
Spruce (and for the North aud Northwest the 
White Spruce), the White and Red Pines and 
the Hemlock Spruce are all fine trees after 
the Norway Spruce aud Balsam Fir have out¬ 
lived their beauty; but the two latter are 
beautiful while young, and should be planted 
so ns to be cutaway when the former half-a- 
dozen kinds require their room. 
Waukegan, 111. 
PROM ELLWANGER & BARRY. 
Omitting the Common Norway Spruce nnd 
Balsam Fir, the following will make a good 
collection of hardy evergreens for grounds 
two to three acres in extent. White Spruce 
(Abies alba); Hemlock Spruce (A. Canaden¬ 
sis); Conical Spruce (A. conica); a dwarf 
variety of Spruce (A. pumila com pacta); 
Eastern Spruce (A.orientails): (Colorado Spruce 
(A. pungens); Nordmatin’s Silver Fir (A . Nord- 
mauuiana); Austrian or Black Pine (Pinus 
A ustriaeu); Dwarf Mugho Pine (Piuus 
Mugho); Scotch Pine or Fir (Pinus sylves- 
trist; Swiss Stone Pine (Cembra): White 
Weymouth Pine. 
Rochester, N. Y. 
FROM TOE STORES & HARRISON CO. 
We should name the following list for plant¬ 
ing: Cypress Nutknensis, Abies Nordmann- 
iania, Hemlock Spruce, Hovey’s Golden Ar¬ 
bor Vita?, Retinispora plumosa, Retiuispora 
pisifera. 
Painesville, O. 
FROM .JOSIAH HOOPES. 
Among the spruces I especially admire Pi¬ 
cea pungens, orientalis, polita, allm,and what 
is known as Alcocquiaun although really 
Ajancusis. [It. is a coincidence and one grati¬ 
fying to the R. N.-Y. that Mr. Hoopes, one of 
our first authorities on conifers, should have 
named the very spruces that, at the risk of 
wearying our readers, we have pressed upon 
t heir attention during the past three or four 
years. That our readers may not be confused, 
we may explaiu that Mr. Hoopes uses Picea 
the new generic name of the spruce, and the 
old generic name of the fir instead of Abies, 
the old name of the spruce, and the new name 
of the fir. It was a bad business to have 
changed these Did, Well-known names.—E ds.] 
In Silver Firs there are very few species but 
what are superior to the Balsam, excepting in 
the younger years of the luttor. My selection 
for this latitude would be Abies concolor, 
Nordmqimiaua, Sibcrica (although of slow 
growth) which is the Picbta of most collec¬ 
tions; and for favorable locations Cephaloni- 
ca and nobilis. 
There is but one species of hemlock to plant 
here, and that is the common eastern formTsu- 
gaCanadensis, The closely allied genus Pseudo- 
suga with oue representative—P. Douglasii— 
furnishes a valuable ornamental tree wheu 
grown from Colorado good, but a miserable 
failure from that gathered ou the Pacific 
Coast. 
West Chester, Pa. 
SUBSTITUTES FOR THE NORWAY 
SPRUCE. 
PETER B. MEAD. 
I have been asked to name some evergreen 
trees that I prefer to the Norway Spruce or 
/ 
I 
