B. P. Weinberg

Magnetic Expedition along the Yenisei from Krasnoyarsk to Dudinka in the Summer of 1912

(author’s abstract).

Owing to delays in obtaining, through the Tomsk Technological Institute, the authorization of the Ministry of Public Education for my assignment, and to the impossibility, before that time, of obtaining from Tomsk University the Wild magnetic theodolite and the Hildebrand astronomical theodolite, with which the University administration had agreed to supply me for this expedition against a deposit of their value, V. D. Dudetsky and I did not manage to take the government steamer Lena, which was leaving on 18 June from Krasnoyarsk for the lower reaches of the Yenisei as far as the Arctic Ocean (to Dikson Island) and was to return at the beginning of August. Having no possibility of waiting for the next steamer, since it was due to return to Krasnoyarsk only at the end of September, we decided to confine ourselves to a somewhat shorter route and, thanks to the kindness of I. K. Okulich, who at that time administered the state properties in the Yenisei province and was in charge of the government steamship service on the Yenisei, chartered the 7-horsepower towing steamer Rassyl’nyi, which was to take us to Dudinka and back to the mouth of the Kureika River by 8 August. By that time an expedition of English and Russian merchants headed by Prof. Ozerov was to arrive there and proceed on this steamer up that river to investigate graphite deposits. If, however, it had not arrived there by 10 August (which, owing to the absence of telegraph and even postal communications, we could learn only on the spot), the same Rassyl’nyi was to take us back to Krasnoyarsk.

We managed to set out only on 17 July—and we were compelled to hurry greatly in order to reach the Kureika by the appointed date: as far as possible to reduce the time and number of stops, to use for observations those morning hours when the crew was still asleep and steam was being raised, and so forth. Nevertheless, thanks to the fact that the steamer was at our complete disposal, we had the possibility of making observations wherever we considered it necessary, and of carrying them out at a far greater number of points than would have been possible when traveling on a passenger steamer¹.

Since there was still room in the wheelhouse of the “Rassypnoy” for the crew, a boat was assigned to “Rassypnoy” at Yeniseisk for us and for the instruments—a small sea rescue boat with a canvas top fitted to it for protection from wind and bad weather. Both “Rassypnoy” and our boat were loaded with coal, which in the lower reaches of the Yenisei could be obtained only from the lighters of the state steamship line. The supply of coal we carried made it possible for us not to make unnecessary stops—all the more so because in those parts even firewood could not be procured everywhere where it would have been desirable; moreover, when the boiler was fired with wood, sparks from the stack in calm, dry weather forced us constantly to water the boat’s canvas with water so that no fire would occur. The bow of our boat was fastened to the stern of the tug by two ropes—and in windy weather (especially when a “siver” blew for several days), the canvas roof acted like a sail, and the swell, purely marine in character in the lower reaches of the Yenisei, where its width in places reaches 10–20 versts, tossed the boat in every direction so that these ropes would alternately slacken and then immediately become taut. In the latter case the jolts were often so sharp that it was impossible to keep one’s feet. These jolts occurred not only in the longitudinal direction but also vertically and transversely; moreover, since the point of attachment of the ropes lay above the boat’s center of inertia, these jolts were sometimes accompanied by a sharp heeling, reaching 30–35 degrees to one side. We note these circumstances for judging our measurements of time by chronometers, whose behavior even under these transport conditions was sufficiently satisfactory.

Despite all our efforts—to move ahead in every kind of weather, to make the fullest possible use of stopover time, and to reduce this time as much as possible—we, partly because of repeated “sivers,” were in Dudinka only by the evening of August 3 and came back to Kureika only on the evening of August 9, but found no one there. After waiting another day and devoting it to observations, on the morning of August 11 we set off back upstream; moreover, the comparison of the speeds of the “Rassypnoy” in the upper parts of the Yenisei, in the lower ones on the way down, and in the lower ones on the present return journey promised little good in the sense of a timely return and compelled us once again to hurry and hurry… The economy of time went so far that for several nights the two of us took turns keeping watch on the “Rassypnoy,” maintaining the fire under the boiler so that the crew, as soon as they awoke, could set out, without spending time raising steam. Toward the end of the journey we were satisfied when, on a stretch, the speed turned out to be 5½–6 versts per hour, whereas downstream we had passed the same sections at a speed of 15 versts per hour. To complete everything, beyond Kholmogorovo the pressure gauge at the boiler broke down—and we had to return to that village and continue the journey with the help of horse traction for our boat. The northerly wind that arose seemed to have hastened our movement, but near Antsiferovo, where the current of the Yenisei turns from a south-to-north direction to an east-to-west direction, this wind began to drive us toward the bank, run us aground, and the waves began to wash over us; in order to get off the shoal we ourselves had to climb into the water—and we barely dragged ourselves to Antsiferovo, where we left the boat and went by horses to Yeniseisk, whence on a passenger steamer we arrived in Krasnoyarsk on September 2.

Under such travel conditions it was impossible to strive at all costs for completeness of observations—and at times we were quite satisfied when, after 1–2 hours of waiting, we managed to take even a single sighting of the sun, and the like. But nevertheless, we were so favored—

The weather favored us, so that at almost all points we could make observations without a tent, the use of which was difficult when two observers were working simultaneously. During long stops we resorted to the tent, among other things, for protection from the midges, which covered the observer’s exposed parts of the body in a continuous layer; spraying the inside of the tent with Dr. Malinin’s anti-mosquito liquid made it possible to work in the tent for about 10 minutes without nets and chamois gloves.

Our good fortune with the weather was expressed chiefly in the fact that, if not on the way there, then on the return trip, at almost all the required points we managed to catch the sun,—and as a result, out of 40 observation points, 30 may be considered “complete,” since each point accounts for the determination of 2.3 elements. There were 23 points where all three elements were determined; at 5 points only 2 elements were measured (at 2—$\delta$ and $I$, at 2—$H$ and $I$, and at 1—$\delta$ and $H$), and at 12—one (at 10—only $\delta$, at 2—only $I$).

The average distance between points, if counted along the river, is 49 versts, and “by field route”—66 versts, and one can only regret that lack of time deprived us of the possibility of making observations at several of the points twice: on the way there and on the way back. In the density of the distribution of points our route along the Yenisei considerably exceeds the conditions set by the Magnetic Commission of the Academy of Sciences for route surveys in Siberia; as for the accuracy attained, our measurements are only slightly below the Commission’s standards—at least insofar as absolute values of the magnetic elements are concerned.

The results of the determinations are placed in Izv. Tomsk. Tekhn. Inst., vol. 37, 1915 (and also in my summary of magnetic determinations in Siberia, printed in Izv. Inst. issl. Sib., 1, 1–69, 1920); a detailed article, written in 1914 and containing about 3 printed sheets of text and tables, has for the time being been deposited, in typewritten form, in the library of the Institute and with the Magnetic Commission of the Academy of Sciences (the same applies also to my other works, of which only the abstracts are placed here). For lack of space I shall confine myself to the report on the expedition printed above and to a few indications of the degree of accuracy of the determinations.

In addition to the above-mentioned Wild and Hildebrand instruments, just before leaving Krasnoyarsk I received a Moureaux instrument belonging to the magnetic observatory of Novorossiisk University and kindly placed at my disposal. Since it had not been studied by us beforehand, we used only its inclinometer (in view of the difficulty of setting up the galvanometer of the Wild instrument) and sometimes also used it, as being more quickly set up, to determine the direction of the magnetic meridian.

Although the Hildebrand was set up directly on the ground, which was rather unsteady at many points, thanks to the precautionary measures taken (the invariability of the observer’s position when sighting the sun and when reading the levels), this unsteadiness had little effect on the results, as is evident from the considerable constancy of the zenith point on the vertical circle and from the good agreement of the chronometer correction values from separate sightings at one and the same point: the mean deviation exceeds 3 seconds only in the case of observations close to noon or made under unfavorable conditions, and at most points it fluctuates between 0.5 and 0.9 sec.

The rate of working chronometer No. 919 was corrected on the basis of comparisons of it with the others (corrections within the limits of $+1.1$ and $-3.1$ sec.). Since the corrections to Tomsk time, computed from the observations on the basis of the values of the latitude $\varphi$ and longitude $\lambda$ of the points, taken from the atlases of Vilkitskii and Bliznyak or taken from other sources, gave val...

values close to one another, but nevertheless differing more (mean deviation $\pm 9.7$ sec.) than would follow from the errors of the observations themselves and from possible irregularity in the chronometer’s rate; accordingly, for these deviations of these corrections to Tomsk time from the mean rate, either the value $\varphi$ was corrected, if the observations were close to noon (we were usually deprived, as explained above, of the possibility of choosing the time), or the value $\lambda$, if there was confidence in the correction, or partly $\varphi$ and partly $\lambda$. The following table gives a summary of such corrected coordinates.

In view of the uncertainty of the values of $\varphi$, computations of the azimuth were made with the adopted values of $\varphi$ and with values greater by $2'$; and in the article, besides the azimuth values, the measures of its change when $\varphi$ is changed by $+2'$ are also given. These changes proved to exceed $5'$ only for observations close to noon, whereas the mean deviation of the azimuth values from individual pointings from the mean at a given station reaches $1'.1$ in only one case.

Just as considerable is the uncertainty in the correction for the diurnal rate according to the observations of the Ekaterinburg and Irkutsk observatories, so that, in general, the values of declination reduced to the epoch 1912.8 have an error of the order of $\pm 5'$.

Wilde’s instrument was compared before V. D. Dudetskii’s trip at the Irkutsk Observatory, and the reduction factor proved to be somewhat different than in 1910. Since the deflections were observed before Vorogov at a short distance, at Vorogov and Osinovskii—at both a short and a long distance, and at more northern points—at a long distance, then, in view of this possibility, at Irkutsk, besides the period of oscillations \(T\), the deflections \(u_1\) and \(u_2\) were observed at the short and at the long distance. The following table gives the results of determining from these observations the corresponding reduction factors \(B_1\) and \(B_2\):

The uncertainty in the values of \(H\), caused by the correction for the diurnal variation and by observational errors, is of the order of \(0.0001\) C.G.S. unit.

Owing to the fact that Moureaux’s inclinometer had not been checked and studied beforehand, the values of the inclination \(J\) must be regarded as having errors of the order of \(5—10'\).

B. P. Weinberg.

Note on the Minimal Value of the Horizontal Component in the Krivorozh Basin according to the Magnetic Surveys of P. T. Pasal’skii in 1899 and 1900.

In the posthumous work of P. T. Pasal’skii, “On the Study of the Distribution of Magnetism on the Earth’s Surface” (Zap. Nov. Univ., 85, 1—547, 1901), on p. 250 it is said:

“The extreme limits of the horizontal intensity were found by us:

On the same p. 110 P. T. Pasal’skii wrote:

“In September 1900 I set out for the region of the magnetic anomalies I had investigated near the Zheltaya River with the special purpose of making observations of variations of terrestrial magnetism and chose for this purpose

1. From the point of view of expenses, chartering the Rassyl’nyi increased the projected cost of the expedition, which amounted to 1131 rubles, whereas the Council of the Institute had allotted us 880 rubles. The total expenses also include the allowance to student V. V. Reverdatto, whom we had sent in the spring to Dudinka to install variation instruments there, but whose principal purpose in traveling was botanical research (for the results, see “Observations made in the summer of 1912 in the lower reaches of the Yenisei River, and a list of plants collected there”—Proceedings of the Society of Naturalists and Physicians at Tomsk University for 1913, 125–174, 1915).

   Unfortunately, observations with the variation instruments ceased soon after V. V. Reverdatto’s departure for the lower reaches of the Yenisei, and his lack of information about our delay, together with the supposition that our journey had not taken place at all, prompted him to take these instruments away on the return trip; we learned of this when we met the schooner Omul at Igarka on 1 August. Thanks to this meeting, we made the rest of the journey not with one chronometer, No. 919, belonging to the Institute’s physical laboratory, but with two more (Erickson No. 134 and No. 670), kindly made available to us from the Omul by V. P. Isachenko. ↩