means of a method first employed by Professor Pupin, been artificially given
electric characteristics which make possible, on the one hand, a more distinct transmission
of speech over long lines, and, on the other, allow of the employment of a
cheaper material (wire of smaller dimensions) in the construction of such lines. The
total length of the Telegraph Service’s loaded bare wire- and cable circuits was,
at the close of 1913, some 29 967'6 km. On the whole, it may be said that
Sweden possesses one of the best constructed long-distance networks in the world.
A practical application of the progress made in telephone technics is the
so-called phantom lines, or the arrangement that three conversations are
transmitted simultaneously on two lines. As a result of the calculations and inventions
of Professor Pleijel, the devices employed for this purpose in the State
telephone network have reached an exceedingly high degree of perfection, and,
at the close of 1913, there were in Use 9 846 km of such superposed connections.
I t is two officials of the Telegraph Service, C. E. Egner, 0. E., and the
principal of the Service’s training school, G. Holmstrom, 0. E., to whom
should be ascribed the honour of having invented the first practical strong-
current telephone for use on long lines. By its means, a conversation can,
without difficulty, be carried on over unloaded lines of ordinary dimensions
between Stockholm and Paris. The patent for Sweden has been bought by the
Telegraph Service, and a fairly large number of instruments is already in use.
Switeh-boards and telephones were, at the beginning of the State Telephone
Service’s existence, for a long sequence of years, supplied by L. M. Ericsson’s
world-renowned factory, in Stockholm. Afterwards, however, the workshops of the
Telegraph Service gradually began to provide, on an ever increasing scale, the
telephones that were needed, and the establishment in question has also designed
and executed most of the new plants and carried out the necessary work for the
maintenance and improvement of the offices. Since, as mentioned above, the
Swedish Telegraph Service was among the first administrations that realized the
necessity of, and carried out, the change) from single lines to double ones,
the exchange apparatus necessary for the new line-system had to be invented
and constructed within the country. The switch-board system employed at the
central and sub-exchange offices are, therefore, as a rule of Swedish manufacture.
The distribution system applied in Stockholm and Gothenburg, which has, too,
been adopted at Hamburg for an 80 000 lines’ plant was the invention of A.
Aven, telephone controller. The central-battery system, introduced at a number
of other offices, such as Malmo, Norrkoping, Halsingborg, Jonkoping, Gavle,
etc., is a modification of the world-renouned system invented and manufactured by
the firm of L. M. Ericsson. Essential improvements in the old magneto system,
which is still made use of at smaller and medium-sized stations, have been elaborated
chiefly by A. H. Olsson, line-engineer, and have been utilized at the
stations at Harnosand, Karlstad, Kristianstad, Vasteras, Ostersund, etc. Automatic
exchange-stations, although on a small scale, on a system invented by G.
A. Betulander, C. E., engaged at the workshops of the Telegraph Service, have
been in use since 1903, and very promising experiments for larger stations have
been made by other officials of the .Service.; A central exchange for 2 000 subscribers,
with a semi-automatic system on an American model, has just been
opened at Landskrona.
Chiefly in consequence of the well devised and well executed exchange systems,
but also as a result of systematic selection, exercise and superintendence of the
staff, the rapidity of service in the State telephone — offices has reached such a
degree of excellence that what, in many other countries, is merely a heart-felt
wish, is in Sweden already an accomplished fact. Even some ten years ago,
the average time elapsing between the subscriber’s making a call and his obtaining
a response from the attendant, at the largest exchanges in Sweden, had been
reduced to, or below, 5 seconds, and at the newer stations, such as those at
Malmo and Halsingborg, statistics show an average wait of 2a seconds, and
even less, for such reply.
Finally, some figures may be given respecting the economic results of
the administration of the Swedish telephone service. The means which
are required for the continued development of the State telephone system,
were, before the year 1911, placed at the disposal of the Board of the
Telegraph Service chiefly in the form of loans, for which the Telegraph
has paid interest, and which had gradually to be amortised by the Service,
and this, as a rule, in a very chort period (12 to 20 years). From and
including the year 1911, however, public grants have been made for the
purpose in question, these amounting, for each of the years 1912, 1913,
and 1914 to 4 million kr. (the grants given in 1913 and 1914 were, to a
certain, small amount, also intended for telegraph purposes); for
1915, the grant amounts to 4 650 000 kr., inclusive of 50 000 kr. for
radio-telegraphic (wireless) purposes. The capital, consisting of such
supplies together with the Telegraph Service’s own profits, which had
been sunk in the State- telephone network had, at the close of 1913,
amounted to 65 994450 kr., 42 971 306 kr. of which was sunk in the
local networks, and 23 023 144 kr. in the long distance network. I f
respect be paid not only to the plant investment, but also to the whole of
the capital disposable for the telephone system, this latter amount during
1913 came to 67 335 639 kr., of which 43 844 601 kr. were for the local
net, and 23 491038 kr. for the long-distance network. Now, as the
surplus obtained from the business, i. e., the difference between the receipts
and the expenditure, amounted, for the local network to 2 576 782 kr. and
for the long-distance net to 2 576 782 kr., it will be seen that the local
telephone network of the Telegraph Service yielded, during the year, a
return of 6 %, and the long distance net one of 14 %, on the capital available
for ; the respective branches of the business. The surplus yielded by the
entire telephone system amounted to 8-8 °/o of the capital (in 1912 to
9-6 %), a result which, if we take into consideration the low terms of
subscription and charges for conversations, and the very extensive right
to free calls possessed- by subscribers at many places, must be considered
as yery satisfactory indeed.
In the figures given above for capital investment in the State telegraph
and telephone systems no capital invested in land and buildings
is included. For the purpose of buying sites and constructing buildings,
means have been supplied in various ways, for the last few years in the
form of grants, amounting for 1913 to 400 000, and for 1914 to 500 000
kr. At the end of 1913, the prime cost value of assets of this kind,
belonging to the Telegraph Service, amounted to 9 696 940 kr. The
net income of this branch of the business, however, only amounted to
155 896 kr., or 1-6 % of the average capital, the reason for these low
figures being that a very large part of the investment during 1913 was