Part 2

In 1853 Hjorth negotiated with a certain Dr. Watson, who had constructed a »dry battery« by means of which Hjorth had meant to drive his electro-magnetic machine. The object of their negotiations was to buy out Hjorth’s above-named partners, and to form a new company for the purpose of exploiting the above-mentioned two machines. The partnership, however, was not realized, and in spring of 1854, Hjorth himself commenced to have a 3 HP battery built in Copenhagen. The machine was fitted with cast iron magnets, and in all probability it was similar to the project of March 1854, and agreed with the patent of October, the same year.

This patent specification reads as follows: »The main feature of this battery consists in applying one, two, or several permanent magnets _A_, of cast iron, and shaped as shewn in the drawing (Figs. 4 and 5), in connection with an equal number or more electro-magnets _B_, shaped as indicated in drawing, in such a manner _that the currents induced in the coils of the revolving armatures are allowed to pass round the electro-magnets; consequently, the more the electro-magnets are excited in the said manner, the more will the armatures C be excited, and the more electricity of course induced in the respective coilings_; and while a mutual and accelerating force is produced in this manner between the electro-magnets and the armatures, an additional or secondary current is at the same time induced in the coiling of the electro-magnets by the motion of the armatures, the said current flowing in the same direction as that of the primary current, after having passed the commutator. The direction of the current induced in the coils of the armatures will, of course, be reversed according to the change of the respective polarities, and the commutator _D_ is therefore applied for the purpose of causing the current to flow constantly in one direction«. Then follows a description of the commutator of the dynamo. Finally the pole-shoes, or false poles, provided on the magnets as well as on the armatures, are mentioned. He points out that the false poles have on the side of attraction, a long straight edge, as distant from the centre as possible, while on the side of separation, either one has a sharp point, nearer to the axis of revolution, »all with a view to avoid reactionary currents, and at the same time to facilitate the motion of the armature«. »While steel magnets also may be applied instead of cast-iron magnets, the permanent magnets may be coiled like the electro-magnets, which also will serve to make them more permanent«.

From the above-named sketch-book notations, and the patent specification, it will be seen that Hjorth, during the years 1851-54, has repeatedly pronounced the dynamo principle with perfect clearness, and that he has utilized it in several projects.

It is worth noting that Hjorth’s so-called »permanent« magnets are of cast iron. This shows that Hjorth has known of remanence, or permanence. He has known that cast iron always possesses some slight magnetism, either induced by the earth magnetism or as a remnant--remnant magnetism--left over from its being magnetized in a coil. It has heretofore been assumed that Siemens was the first to call attention to this property of iron, in his paper in the transactions of the Royal Society, of the 14th of February, 1867.--Thus Hjorth used this weak remanent magnetism in the large cast iron magnets to produce the initial current in the dynamo, which then excites itself.--At the end of the patent specification, Hjorth points out that the remanent magnets may also be coiled (compare Fig. 2), and thereby he comes closer to the later dynamo constructions.

Hjorth is quite right, according to the patent specification, in giving the pole-shoes such a shape that the armature is gradually demagnetized, and in stating that the object of this is thereby to avoid reactionary currents, and consequently the formation of sparks; while he is mistaken in believing to be able to facilitate the motion of the armature by giving the pole-shoes a certain special shape, because in that case, the machine would be a _perpetuum mobile_.

Together with the above-mentioned dynamo, Hjorth had an electromotor made in Copenhagen, essentially similar to the one exhibited in 1851. When in the autumn 1854 the machines were finished, Hjorth was called back to England, in order to continue the work on his inventions. It is not known whether the machines were sent to England or not; at any rate they aroused some interest there, and he had a new and larger dynamo built by Messrs Malcolm & Campbell; of Liverpool, 7 India Buildings, at the expense of Malcolm and others. This machine was patented in 1855[6], and is shown in Fig. 6, which is reproduced from a photograph. Here, too, the dynamo principle has been followed, but each electro-magnet is composed of one solid and one tubular electro-magnet, the latter enclosing the former, the two together forming a so-called »_cup magnet_«, a construction which has also been used by later inventors. Hjorth describes the action of the battery as follows: »_The permanent magnets acting on the armatures, brought in succession between their poles, induce a current in the coils of the armatures, which current, after having been caused by the commutator to flow in one direction, passes round the electro-magnets, charging the same and acting on the armatures. By the mutual action between the electro-magnets and the armatures, an accelerating force is obtained, which in the result produces electricity greater in quantity and intensity than has heretofore been obtained by any similar means._« At the same time, Hjorth allowed the dynamo patent of 1854 to lapse, it being merely a provisional patent.

Together with the dynamo patent of 1854, Hjorth secured a provisional patent on an improved electromotor[7], and together with the dynamo patent of 1855, he obtained the complete patent on the above mentioned electromotor, as well as on another construction thereof[8]. The former consisted of hollow, horizontal electro-magnets (cylinders), being of a special shape inside, adapting them to give to an electro-magnetic piston, reciprocating within them, a long and steady stroke. By means of a crank, the stroke was transformed into a rotary motion. The other electro-motor consisted of wheels, with protruding teeth, which were set in rotary motion by the teeth being attracted into hollow electro-magnets.

FOOTNOTES:

[1] According to the usual terminology of those times, an »electro-magnetic« machine means a machine driven by electricity, an electromotor, while, on the other hand, a »magneto electric battery«, or a »dry battery« is a machine for producing electricity.

[2] Specification of Patent No. 12295, 1848.

[3] After the publication of my first treatise in the »Elektroteknikeren«, for February 1907, various parties have objected that Hjorth, in his dynamos, did not use the dynamo principle in its purest form, as he had one large, unwound, cast iron magnet. On the contrary, the above-mentioned leaf of his sketch-book shows that Hjorth, as early as in 1851, has used the dynamo principle in its purest from--exactly the same as used by Siemens in 1867--as all the field magnets have been wound cast iron magnets, and the initial current is induced by the remnant magnetism of these magnets. _S. S._

[4] This is correct, as long as he uses armatures with but a single winding, because, in that case, the number of armature windings is proportional to the number of steel magnets. Whereas Hjorth is mistaken, when in 1867 he makes the same statement about a machine, where nothing prevents the armature from being fitted with a great number of windings.

[5] Specification of Patent No. 2198, 1854.

[6] Specification of Patent No. 806, 1855.

[7] Specification of Patent No. 2199, 1854.

[8] Specifications of Patents No. 807 and 808, 1855.

Hard Times.

In May, 1856, Hjorth returned from England, disappointed. It will be noted that through the electro-motor Hjorth was led to occupy himself with the dynamo machine. The dynamo was built in order to produce motive power for the motor. All the time he was working on these two inventions, it was his firm belief that if he could make the dynamo drive the electro-motor, he would be able to attain a substantial saving in power, get much more power out of the electro-motor than was consumed in driving the dynamo. The machines would, as it were, run automatically. He could not understand, why Dr. Watson was sceptical with regard to this manner of battery action. He intended to install his machines in ships and locomotives, which would then be propelled with a minimum consumption of power. In short, the combination of dynamo and electro-motor imagined by Hjorth was to be a _perpetuum mobile_. It has certainly been the great disappointment of his journey to England, that this scheme failed.

On reading about this mistake, one is inclined to base the judgment of Hjorth upon assumptions belonging to the present time. But this would be a great injustice to him. The axiom that the quantity of energy in nature is unalterable, and consequently a _perpetuum mobile_ an impossibility, has, as it were, been imbued by our own generation with the mother’s milk. Not so with Hjorth. Not until the forties of the last century, did Mayer, Joule and Colding, the City Engineer of Copenhagen, set forth their theories about the permanency of energy, and about the convertibility of heat into mechanical activity, and of the latter into heat again. These theories, however, were very slowly accepted, even by scientists. It is, therefore, no wonder that a man like Hjorth, having no special scientific training, could not easily digest the new theory and Hjorth did not have any instinctive sensation of having entered upon a hopeless and impossible track. On the contrary, he imagined the new wonderful form of energy to conceal unestimable possibilities which he had only to wrest from nature.

Though Hjorth was thus ship-wrecked on his favourite idea, he nevertheless discovered new land, fertile for coming generations. His intrepid zeal guided him, as Ørsted had anticipated, in spite of his lack of scientific education, on to the road leading to the splendid results of this day.

None of Hjorth’s original partners participated in the manufacture of his latest machines, and possibly this was due to his above-mentioned erroneous idea. Only one of his English friends, Wm. Macredie, of Melbourne, maintained his attachment to Hjorth and his confidence in him to the last. He was always very interested in Hjorth’s schemes, and, besides, he shared his religious creed.

Hjorth was very anxious as to his future. When he returned from England, he stood quite destitute and felt depressed by poverty. His health was not of the best, and his formerly so neat hand-writing had become unsteady. He received, shortly after his return, a communication from his English partners that they wished to have the dynamo patented in Denmark and France, which showed that they had faith in this machine, but nevertheless these were hard times for Hjorth.

The dynamo remained for some time with Malcolm, in Liverpool, and negotiations for its sale were several times entered into, but were without results. It was tested on several occasions, but these tests proved that it could not yield as much as might be expected from its size. The uncoiled magnets, which were originally of cast iron, were replaced by more powerful steel magnets. Upon the whole, this dynamo had a rather eventful existence, for first every other magnet pole was removed (see Fig. 6), and then it was proposed to rewind the magnets. In May, 1857, it was donated to the Polytechnic Institute, Regent Street, in London. Among the papers left by Hjorth, there are a daguerreotype and a photograph of this machine, (from which the accompanying Fig. 6 is reproduced).

Notwithstanding a thorough search of the London museums, it has been impossible to trace this machine, which is said to have been seen in London during the nineties.

Hjorth was now compelled to find a new means of earning his livelihood, and to make new connections. In 1857, he became the representative of Cyclop’s Steel Manufactory, Charles Cammell, of Sheffield, and in 1859, he applied for and obtained a licence as a translator of English in Copenhagen. Finally he had a kind of engineering and patent office, assisting strangers in obtaining monopolies, and doing work for new railroads, bridges etc. In the beginning of the sixties he caused a research to be made concerning the use of coals from Hornholm and Silkeborg, and the use of peat for briquettes. In April, 1860, he applied to the government for a position, enabling him to work for the building of new railroads in Denmark, and at the same time he referred to his previous merits in that direction. As he had not, within a year thereafter, received any position, he made a petition for a yearly pension, in case such a position could not be given to him. As »the idea of building the Sealand railroad, as well as the general location of this road, is mainly due to Secretary Hjorth ... and further more, no small share in the completion of the undertaking is due to him«, it was proposed, on the budget for 1861-62, to grant a pension to Hjorth. That year and the following ones, until his death, he received 500 rixdollars.

During these years, Hjorth lived at 10 Nørrebrogade. In 1845, he married Vilhelmine Ancker, née Hansen (born on the 27th of March, 1805), the widow of the farmer Diderick Ancker, of »Lille Egede«, and thereby he became the step-father of two daughters. This marriage was childless.

This carefully dressed little man[9] in top-hat and high-heeled shoes, was well known, and very well liked in many circles. He was always amiable and willing to help, and it is known that he has, at great personal sacrifice, assisted young artisans who were in hard luck. In society he attracted attention by his power of fascination and by his universal knowledge. On Sundays he was regularly seen directing his steps to St. John’s church, where, for many years, he was a member of Rev. Frimodt’s congregation.

During the period of depression above described, Hjorth could naturally not very well afford to occupy himself with experiments, nor had he much time. Still, in 1857, he secured permission to undertake, at the navy yard, some experiments concerning the carrying capacity of a magnet at varying distances between the pole and the armature, and at the same time he sketched out the construction of an electro-motor, especially well adapted to utilize the magnetic attraction. This electro-motor was built in Copenhagen with funds granted by the »Classenske Fideicommis«. When it was finished, Hjorth applied for the money needed to make it double acting.

In autumn 1860, Hjorth was in Paris, and there he worked for his electrical inventions.

In 1866, Wilde published his machine, in which the current needed to magnetize the electro-magnets was produced by a permanent magnet. This is exactly the principle, underlying the dynamos built by Hjorth in 1854 and 1855. Hjorth’s good friend, Wm. Macredie, Melbourne, sent Hjorth a clipping from an English periodical mentioning Wilde’s machine, and called his attention to the identity.

It is to be regretted that Hjorth’s answer is not known, as his copy-book for 1866 has been lost.

Considering the data at hand when Hjorth’s biography was published in 1907, one might be inclined to believe that Hjorth had invented the dynamo principle and then dropped it at once, going back to steel magnets. It is, however, clearly evidenced, by the papers left by Hjorth, that this has not been the case, but that Hjorth has used the dynamo principle, in various, more or less pure, forms, in practically all his projects from 1851 to 1870.

As previously mentioned, Hjorth had been disappointed in his attempts to produce energy through an electrical transmission of power, but this did not cause him to relinquish the idea of producing energy by electric means. He took this up again in a new form in his old age. In order to have this idea carried out in practice, Hjorth had a machine built, a description and drawing of which is to be found in a pamphlet published later on in French and Danish. From this it appears that the machine was not originally built according to the dynamo principle. Hjorth found no advantage in using the expensive electro-magnets, as it was his main object to prove that, by his special arrangement of armatures and magnets, he could reduce the power required to produce a certain amount of electrical energy. The machine, in its manner of construction, reminds one to some extent, of Hjorth’s project of 1851. Two or three rings, or wheels, of armature coils _A_ (see Fig. 7) revolve between three or four circular rows of magnets _M_. This decreased consumption of power was to be attained by offsetting the armature wheels somewhat relatively to one another, for instance so that when one armature of the topmost wheel was opposite one magnet pole, an armature of the next armature wheel would be spaced one quarter of a pole distance from a pole, and an armature of the lowest wheel would be one half pole distance from a pole. As it is well known, this idea is entirely erroneous, it being contrary to the axiom of the constancy of energy.

The machine was built into a casing, and was sent to the Paris exhibition of 1867. Hjorth was always very careful not to give any information about his inventions to anybody. At the end of April, he went to Paris himself. The machine had suffered some injury on the journey, and had to be repaired in Paris, and therefore it made its appearance rather late. Still he succeeded in having it submitted to the judgment of the jury, and a test of electrolytic deposition was made, which proved entirely successful.

In Paris he met a certain business-man who, later on, requested to enter into partnership with Hjorth. This man was an adventurer, whose ambition was to become a Knight of Danebrog. It is only to be regretted that this person obtained so great a power over Hjorth, and understood how to deceive him. The previously mentioned pamphlet, edited by the partner, and named »Batterie magnéto-électrique de Søren Hjorth«, is a document of the poorest kind.

Through his partner, Hjorth was introduced to various electricians and men of science, among others the renowned Samuel B. Morse, who recommended Hjorth’s machine, but took exception to his idea concerning the production of energy.

The electrician who repaired Hjorth’s machine, introduced him to the president of the French Société d’Encouragement, who had proposed a competition for electrical machines, and had offered a prize of 3000 fr. for a machine, complying with the conditions given. Hjorth’s machine was sent to the society, but he did not succeed in obtaining the prize, which was awarded to the subsequently so famous »Alliance« machine. On the 7th of July, Hjorth, probably prompted by his partner, obtained an audience of Emperor Napoleon III. After he had demonstrated his invention, and shown the letter from Professor Morse, the Emperor asked him what he could do for him, and Hjorth answered that his highest desire was to have a larger machine built, and he requested the Emperor’s protection and assistance, in order to accomplish this. The Emperor ordered an examination of the machine to be made. The well-known Professor Jamin was retained as an expert, and Hjorth demonstrated the machine before him. On the following day it was examined, in the presence of Hjorth and his partner, by Jamin and other men of science. They subsequently had the machine sent to the exposition, where they measured the voltage and intensity of current, and expressed their satisfaction, as to the results attained. Nevertheless Hjorth was disappointed to receive, the next day, through the representative of the Emperor, General Favé, a communication that the subvention applied for could not be granted.

At the exposition, a great sensation was created by a dynamo exhibited by Ladd. This machine had two electro-magnets and two armatures, the current being directed from the smaller armature round the electro-magnets and taken from the larger armature to the exterior circuit, lights for instance. Thus the machine was evidently built according to the dynamo principle.

In order to claim his right of priority to this principle, Hjorth went to the prominent authority on physics, Count Th. du Moncel, who later on became the editor of »La lumière électrique«. As Hjorth himself did not know French, the interview probably took place through his partner. About this, Moncel writes in the above mentioned periodical, in 1883, that Hjorth’s representative was not very conversant with electrical matters; therefore he was unable to express himself clearly, and consequently Hjorth’s rights of priority were not acknowledged.

Having received the Emperor’s refusal, Hjorth went home, broken down by illness and disappointments.

In 1868-69 Hjorth, due to the interest taken in his case by the manufacturer Mr. Kähler, succeeded in having a small machine built in this gentleman’s shop in Korsør. At the same time, a larger machine was made in Copenhagen, the necessary funds being contributed by several country gentlemen and merchants interested in the case. Finally, in December, 1868, a body of prominent men addressed the government, petitioning a subvention of 15,000 rixdollars to be given to Hjorth, in order to enable him to build a new and larger machine. As the Ministry was not inclined to grant a sum of this size, it proposed to grant 1000 rixdollars, in order to have the existing machines examined by Professor Hummel and other experts. This proposition was accepted by Hjorth, and a commission was formed, consisting of Professor Hummel, assisted by Professor Holten, Instructor Lorenz and Winstrup, a mechanic. As early as December, 1868, Professor Hummel, together with head-master Ibsen from Sorø, had visited dyer Gülich of Christianshavn, where one of the machines was located, and they made a few tests, which Hummel himself did not consider to be of any importance. The experiments were to be made in April, 1869, after an assistant had made a preliminary experiment, but then Kähler reported that he had taken the machine apart, in order to make an alteration therein, and that this would take a couple of months. It appears, from a letter from Hjorth to the Ministry of the Interior, that Hjorth had arrived at the conclusion that he must resort to the use of electro-magnets, to a certain extent, at least, on account of »the steel, by continued use, losing part of its magnetic power, which necessitates its being re-magnetized«, and partly because »it appears that electro-magnets may be made to yield a considerably larger magnetic power than steel magnets, by means of the electrical current induced thereby«. As this change to the dynamo principle was estimated to cost 400 rixdollars, Hjorth was informed, in April 1869, that this amount would be paid out of the sum, granted for the experiments, when the smaller machine had been re-built.