Colong (De Colong) Ivan Petrovich 
(22.02(02.03).1839–13(26).05.1901) 
 

Russian scientist in the field of marine navigation. 
Born in the city of Dinaburg, Kurland province. Descended from an old family of nobles who left France during the reign of Louis XIV. 
He was educated in the Naval Cadet Corps and Officer Class (later the Nikolaev Maritime Academy). 
From his youth, Colong was fond of mathematics and after graduating from the Officer class in 1861, he attended a mathematical course at St. Petersburg University. Professors such as M.V. Ostrogradsky laid in it the foundation of mathematical knowledge, developing which Colong became famous both in Russia and abroad. 
In those years, armored and iron ships appeared on the fleets, and the traditional magnetic compass ceased to be a reliable indicator of the direction of the ship’s path. Colong joined the study of the magnetism of metal ships and brilliantly solved a number of complex issues on the theory of deviation and the practice of the simplest methods of its destruction. The results of his research were published in the Maritime Collection and were used in the preparation of the relevant guidelines, becoming the property of all the fleets of the world. Colong materialized his ideas by developing and creating a device for the destruction of the deviation - the inclinator. In 1882, he demonstrated the tools he invented to Emperor Alexander III, who awarded him a compass, studded with diamonds with a monogram image of the name of the king. In the same year, the Russian Academy of Sciences awarded him the Lomonosov Prize. A report on this award stated that "the works of Mr. De-Kolong are among those with which the value of the prize itself is elevated". The Academy recognized that De Colong's many years of work, which required deep mathematical knowledge and ingenious considerations, pushed the theory of deviation far ahead and achieved important practical results for the benefit of military and merchant fleets, providing a simple and reliable means of identifying and destroying the harmful effects of shipboard iron and thus providing in this regard safe navigation of vessels". 
Since 1886, after the death of I.P. Belavenets Kolong actually led the compass business in the Russian fleet. In 1889, he was appointed head of the compass business in the nautical instruments workshop at the GSU. The evaluation of the scientific significance of Kolong's works was his election in 1896 as a corresponding member of the Russian Academy of Sciences for physical discharge. Colong successfully combined his scientific work with teaching at the Nikolaev Maritime Academy. 
The other side of his activity was the work at the Maritime Department's cash office, where he was entrusted with complex mathematical calculations to determine the amount of pensions and various benefits. On the basis of probability theory and statistical data, Colong compiled practical calculation formulas, the correctness of which was confirmed by life. For these his works in 1871, Kolong was awarded the Order of St. Vladimir, 4 degrees. 
In 1893, he was given the rank of Major General, and shortly before that, he took the post of deputy head of the State University of Georgia. About the dedication of Kolong in the work says the fact that in his 43-year service record in the column of vacations and being out of the service briefly said "was not." Noting the merits of Kolong, A.N.Krylov wrote: “It should be noted that the study of the deviation of compasses, thanks to the works of I.P. de Colong, covering a time span of about 40 years, stood in our fleet much higher than in any of the foreign fleets ... Along with Poisson, A. Smith and V. Thomson, Ivan Petrovich is a true creator of this field of knowledge, so important for navigation, and now for aviation”.  
He died in St. Petersburg. Buried at Smolensk Lutheran Cemetery. The grave could not be found. 
The peninsula and the cape (De Kolong) on the Zarya peninsula on the bank of Khariton Laptev on the Taimyr Peninsula. Named by E.V. Toll in 1900 after the compass shooting. 
Bay on the bank of Khariton Laptev on the peninsula of De Kolong. Named no later than 1962 by Soviet researchers.