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fish, but trout-breeding is much hindered by the presence of less valuable kinds, such as roach and perch. The further increase of such species must be prevented by systematic clearing. Often in these cases, recourse must be had to artificial stocking with trout, and a rapidly growing species such as the Moosach-trout is to be recommended. Further, grayling, barbel and perch deserve recognition as non-migratory fish, while Trutta iridea can be bred at the same time as these species, for there is a plentiful supply of food and this fish will contribute to the profits and lengthen the fishery season. The breeding of brook-trout will not suffer in any way, provided roach, perch and pike are exterminated.
54 - The Use and Cost of Electricity in Agriculture.
KEYSERLINGK (von). Ueber Verwendung und Kosten der Elektrizität in der Landwirtschaft.
(A Lecture given at the third general meeting of the Silesian Vereinigung für Wirtschaftslehre des Landbaues in Breslau, May 8. 1912). — Archiv für exakte Wirtschaftsforschung, Vol. 4. Part, 3, pp. 432-441. Jena, 1912.
The writer gives in the first place a clear explanation of the expressions and terms used in electro-technique, such as energy, power, metrekilogramme, horse-power, ampére, volt and kilowatt-hour.
Then he enters into a description of some agricultural undertakings which are provided with electricity. The estate of Wilkau, which consists of 3642 acres of arable land and pasturage, and possesses livestock including 170 cows, 200 pigs, 40 horses and 60 draught oxen, has had since 1900 an electric plant with a dynamo with an output of 6.5 kilowatts and driven by about II HP.
The necessary force is supplied by a steam engine, which by means of a belt drives also directly a chaff-cutter, a mill and a grindstone. The secondary plant consists of 57 incandescent lamps, 2 arc-lamps, a 6 HP. motor for the dairy, a 1.2 HP motor for the water pump, and a portable motor of 12 HP.
An accumulator battery of 24 kilowatts supplies the current when the engine is not running.
The second estate with an electric plant is that of Piskorsine, which has a workable area of 2655 acres and live stock including 176 milch cows, 23 horses and 36 draught oxen.
The power is obtained from a suction gas motor, which works on a main shafting which by belting drives an oilcake crusher, an oat roller, a mill for crushing grain, a chaff cutter, the compressor for the “ Mammut pump, as well as a dynamo of 7.5 kilowatts. In the electric secondary plant, there are 140 incandescent lamps, 3 arc lamps, three 2 HP. motors and a portable motor of 2/3 HP. The accumulator battery can produce 20 kilowatt hours.
The Guckelwitz estate has a workable area of 1942 acres, and 115 cows, 13 horses, and 48 draught oxen.
Here there is also an central electric station consisting of a dynamo of about 15 kilowatt performance, which is directly coupled with a Diesel motor of 20 HP maximum power. The secondary plant consists of 71 incandescent lamps, 5 motors, of 3, 12, II, 4 and 3 HP, together with a portable 2 HP granary motor.
The three estates of Klettendorf, Bettlern, and Lohe are connected with the Klettendorf sugar factory central electric station.
The Klettendorf estate includes a workable area of 2949 acres and
keeps 160 cows, 32 horses and 54 draught oxen.
It receives a continuous current with a tension of 110 volts. The secondary plant includes 85 incandescent lamps, a 22 HP motor as well as a 9.5 H.P. motor and a portable 3/4 HP motor.
The Bettlern and Lohe estates, on account of their distance from the sugar factory, have a polyphase electric installation. The current is supplied to the estates with a tension of 5000 volts and there transformed to the required tension of 210 volts.
The electric plant of Bettlern (which estate consists of 3076 acres of workable land and possesses 205 cows, 36 horses and 50 draught oxen) includes 153 incandescent lamps and 6 motors of 25, 7.5, 5, 1, 3 and 10 HP.
On the estate of Lohe (workable area 2104 acres; live stock: 132 cows, 23 horses, 26 draught oxen) there are 118 incandescent lamps and 6 motors of 32, 10, 4, 2, 1, 3/4 HP. After describing these 6 electric plants, the writer turns to the question of their cost.
The instalment cost at Wilhau was £563 10s., at Piskorsine £1401 8s., at Guckelwitz £2205; at the three estates of Klettendorf, Bettlern, and Lohe (which have no primary station of their own) the expense was £367 10s., £980 and £ 739 18s. respectively, without reckoning the outlay on alterations, or building. The cost of working the electric machines amounted on the three estates which have their own primary stations, and each requiring the service of a thoroughly trained mechanic, to £63 145. and on the other estates to £24 10s. per annum per estate. cleaning and repairs were £15 175. to The cost of fuel was:
The expenses of grease, £39 4s. per estate per annum.
At Wilkau, with own steam plant
At Guckelwitz with Diesel motor
without interest or amortisation.
Through the electric-meter the following amount of current was registered as used per annum:
The reason of the great difference in the amount of electric force used is that at Wilkau and Piskorsine, the engines requiring most force are not driven directly by electricity while at Guckelwitz and on the other estates direct electric force is used for all the engines. Further, Klettendorf and Bettlern also drive the grain crusher, oat roller and oil-cake crusher belonging to two other neighbouring estates. For this reason the cost of the single kilowatt hour, also in Wilkau and Piskorsine, can only be accurately estimated if it is known what part of the expense was incurred by the engines which were directly driven without electricity. In Guckelwitz the average annual cost of the kilowatt hour, in the last two years, exclusive of interest and amortisation was, 1.2d.
This sum per kilowatt-hour represents the expense of a modern electric primary plant suitable for such an estate at the present time.
If it is considered that the cost of the interest on the capital and the amortisation of the plant, is not included and that it is not always well to sink much capital for many years in installing an electric plant, the above figure may probably be considered as affording data for estimating the price of a current supplied from a central station by overhead conductors.
The writer adds to these figures other observations.
If threshing could be performed by electricity at Guckelwitz, the cost of the kilowatt-hour would be lower, for the annual consumption of force would be considerably increased without raising the working expenses. On the other hand, the expenses of interest and amortisation would greatly rise, so that the whole cost of the plant would remain unchanged.
If, as in Guckeliwitz, the motor only drives the dynamo, and all the other machines are driven by separate electric motors, the advantage is gained that each machine can be set going at will and work separately without incurring the loss of force entailed through a principal beltgearing.
The writer considers that the Diesel motor wears well as a driving motor, uses little fuel, is seldom out of order, and costs little for repairs; it is thus much more satisfactory than the suction gas motor or the steam engine.
Electric threshing makes great demands on the central electric station: the Diesel-motor and the dynamo have to be nearly twice their usual size, which results in a larger amount having to be set apart for interest and amortisation.
If it is required to drive a modern threshing machine with pneumatic straw stacker (a 63 inch fan drum; hourly performance about 40 cwts.) by electricity and make the straw into bales by means of a straw press at the same time or to chop it and to stack it with a pneumatic elevator on the spot, a motor of at least 30 HP must be selected. To drive "Mammut" threshing machine of about 40 to 50 tons performance daily, a motor of at least 80 HP is required, if the straw is to be pressed or chopped at the some time. For the motor power must be equal to the greatest demands which may be made on it, in order that there may be no interruption of the work. Assistance may be afforded by providing the motor with a fly-wheel; this, like the weighty portions of the steam-engine when in motion, more or less counterbalances the unavoidable sudden variations in the power required during threshing operations.
The question whether threshing by electricity when attached by over-head conductors to a central station is preferable to threshing by steam, must be decided on the merits of each individual case. The answer depends upon different circumstances: e. g. the amount of space available for threshing, the expense of the electric conductors and whether the steam-threshing plant is new or not.
Portable motors are much to be recommended for driving winnowers, sorters, grindstones, machines for making straw ropes and any other machines which do not require much force. The use of apparatus for starting or stopping motors to drive water-puinps, by means of floats in the tanks which automatically throw them into or out of gear and thus make the pumps self-acting, is also very advantageous.
With regard to the systems of lighting, arc lamps entail a good deal of work, and as on a farm the suitable staff is usually lacking, incandescent lamps are better.
All lamps should be distributed as well as possible and the switches should be placed in easily accessible places.
The best switches are those with patent keys, as they can only be used by the person whose duty it is to turn the light off and on. In large stables multiple switches are to be recommended. In order to lengthen the working time in the winter and autumn months, the barns should also be lighted by electricity. A lamp of high candle power should also be affixed outside the threshing-floor, in order that the mechanics. may have sufficient light to attend well to the engine.
All the advantages and conveniences, which electric lighting affords are, according to the writer, bought at a very high price. The expenses of lighting a unit of the workable land by means of petroleum and spirit amount on an average to 1.8d per annum and acre, in the case of twelve estates where electricity was not employed (workable area 24 172 acres).
The expense incurred on the six estates, where electricity was used in addition to other illuminants was 0.58d. per year and acre (workable area 16 360 acres).
On the six last estates, the cost of the electric lighting only amounted to 2/3 of the total expense of illumination of 1.8d. per year and acre and thus should only have amounted to 1.22d.; in reality, however, the cost was about 2.45d. per year and acre.
Adding to this the 0.58d. expended on petroleum and spirit on the six estates where electric light was used in addition, the total lighting expense per year and acre (not including interest and amortisation) was about 3.03d.
It can therefore only be decided upon the merits of each separnte case, whether the advantages offered by electric lighting justify the additional expenses incurred in its use, and further, whether electric light shall alone be employed or electricity also be used as the source of
The electric motor possesses the great advantage of fulfilling all the requirements for driving machines and of doing this in a more satisfactory manner and with less expense for reconstruction or building than is entailed by the use of any other engine. Also it needs very little
The writer had only negative results in the electric plough experiments which he carried out in 1902, on account of the loss in the continuous current conductors and because the motors used were not sufficiently powerful.
Since that date, however, much progress has been made in electrical science, on the one hand from the use of high tension polyphase electric currents, and on the other hand from motors having been devised which correspond to the actual needs of ploughing operations.
55- The Capitalization Value of Real Estate.
LAUR, ERNST.: Der Ertragswert der Liegenschaften. Zeitung, Year 61, Part 21, pp. 705-721. Stuttgart, November 1, 1912. In No. 2 of the Archiv für exakte Wirtschaftsforschung, 1912, the writer has published a paper upon the estimation of the capitalization value of estates from the gross farming returns (1). He showed how the capitalization value can be better ascertained by a property valuation based upon the gross returns. The direct estimation of the gross returns, and the expenditure and the valuation of the estates by means of the net profits thus obtained was rejected as being too difficult.
A few weeks later appeared Prof. Aereboe's new work "Taxation von Landgütern und Grundstücken ". The author also rejects the valuation based on net profits. While, however, Dr. Laur considers the capi
(1) Set No. 1337, B, September 1912.