The article reveals the biographical information of the scientist-inventor, hydraulic engineer, teacher, public figure, one of the founders of the inventive movement in Ukraine, Professor Y. V. Lange (1877−1928) with a direct reflection of his creative searches within the activities of the group of inventors of the Kyiv Polytechnic Society of Engineers and Agronomists at the Kyiv Polytechnic Institute of Emperor Alexander II during 1915−1917. Using the methods of archival and source analysis, a number of important factual events in the life of the scientist are reflected, in particular during his studies at the Moscow Engineering School, the Kyiv Polytechnic Institute of Emperor Alexander II, the New Oleksandriya Institute of Agriculture and Forestry; scientific and pedagogical work in Samara, Poltava, Kyiv, and Kharkiv provinces. His scientific achievements in the field of engineering and hydraulic engineering, which amount to more than 80 works, are analyzed. The issues of organization, structure, activities, and personal composition of the group of inventors are highlighted. The personal contribution of Professor Y. V. Lange to the development of the business during his work in the group was established, particular during his participation in the First All-Russian Congress of Inventors (1916); during the creation of the Department of People’s Inventions, a library for inventors, a research laboratory for research and development of inventions; elaboration of the legal side of state funding of inventions in the country; improvement of the legislative framework in the patent system; development of international cooperation in the field of engineering. It is investigated that the scientist became the founder of the All-Ukrainian Association of Inventors (hereinafter − the Ukrainian Association of Workers-Inventors) in 1925, which was engaged in practical assistance to inventors and protection of their copyrights in the process of developing creative ideas.

1. Hordiyenko, L. V. (2019). Kyyivs’ke politekhnichne tovarystvo inzheneriv ta ahronomiv pry Kyyivs’komu politekhnichnomu instytuti Imperatora Oleksandra II (1911–1916 rr.) : osnovni orhanizatsiyni aspekty diyal’nosti [Kyiv Polytechnic Society of Engineers and Agronomists at the Kyiv Polytechnic Institute of Emperor Alexander II (1911–1916) : main organizational aspects of activity]. Istoriya nauky i biohrafistyka − History of science and biography, issue 2, pp. 138–152. URL : http://inb.dnsgb.com.ua/2019-2/09.pdf [In Ukrainian].
2. Hordiyenko, L. V. (2019). Diyal’nist’ pidsektsiyi «Hurtok vynakhidnykiv» pry Kyyivs’komu politekhnichnomu tovarystvi inzheneriv i ahronomiv (1915–1917 rr.) [Activities of the subsection «Inventors’ Circle» at the Kyiv Polytechnic Society of Engineers and Agronomists (1915–1917)]. Istoriya osvity, nauky i tekhniky v Ukrayini : materialy KhIV Vseukr. konf. molodykh uchenykh ta spets., prysvyach. yuvil. datam vid dnya narodzh. vydatnykh uchenykh v haluzi ahrar. nauk – osnovopolozhnykiv s.-h. dosl. spravy v Ukrayini za nauk. napryamamy, profesoriv – Bohdanova Serhiya Mykhaylovycha (1859–1920), Shyndlera Kamilla Havrylovycha (1869–1940) ta chl.-kor. AN URSR Tyulenyeva Mykoly Oleksandrovycha (1889–1969), Kyyiv, 17 trav. 2019 r. − History of education, science and technology in Ukraine: materials of the 14th All-Ukraine. conf. young scientists and specialists, dedicated. jubilee dates from the date of birth prominent scientists in the field of agriculture. of Sciences − the founders of the village of ex. affairs in Ukraine for sciences. directions, professors − Serhiy Mykhailovych Bohdanov (1859–1920), Kamil Havrylovich Schindler (1869–1940) and member-cor. Academy of Sciences of the Ukrainian SSR of Mykola Oleksandrovych Tyuleniev (1889–1969), Kyiv, May 17. 2019 / NAAS, NNSGB, Council of Young Scientists of NAAS [etc.] ; structure : V. A. Vergunov, A. S. Bilotserkivska, H. M. Dmitrieva ; editor : V. A. Vergunov (head) [etc.]. Kyiv : KOMPRYNT, pp. 67−69 [In Ukrainian].
3. Hordiyenko, L. V. (2023). Diyal’nist’ chleniv Kyyivs’koho politekhnichnoho tovarystva inzheneriv i ahronomiv u mezhakh rozvytku inzhenernoyi, mekhanichnoyi, khimichnoyi ta ahronomichnoyi nauk u period 1911−1916 rr. [Activities of members of the Kyiv Polytechnic Society of Engineers and Agronomists within the framework of the development of engineering, mechanical, chemical and agronomic sciences in the period 1911−1916]. Litopys Volyni – [Chronicle of Volyn], issue 28, pp. 68−73. URL : http://litopys.volyn.ua/index.php/litopys/article/view/411 [In Ukrainian].
4. Demuz, I. O. (2013). Naukovo-tekhnichni tovarystva Ukrayiny kintsya ХІХ – pochatku ХХ st. : istoriohrafiya dorevolyutsiynoho periodu [Scientific and technical societies of Ukraine of the late 19th and early 20th centuries : historiography of the pre-revolutionary period]. Visnyk Kharkivs’koho universytetu imeni V. N. Karazina − Bulletin of Kharkiv University named after V. N. Karazin, no. 1055 : Ser. : History of Ukraine. Ukrainian studies : historical and philosophical sciences ; issue 16, pp. 23−28 [In Ukrainian].
5. Bilotserkivs’ka, A. S. (2017) Kyyivs’ke politekhnichne tovarystvo inzheneriv ta ahronomiv : istoriya stvorennya [Kiev Polytechnic Society of Engineers and Agronomists: History of Creation]. Istoriya osvity, nauky i tekhniky v Ukrayini : materialy KhII Mizhnar. konf. molodykh uchenykh ta spetsialistiv, prysvyach. 100-richchyu vid dnya stvorennya NNSHB NAAN, Kyyiv, 19 trav. 2017 r. − History of education, science and technology in Ukraine : materials 12 International conf. young scientists and specialists, devoted 100th anniversary of the foundation of the National Academy of Sciences of the NAS of Ukraine, Kiev, May 19. 2017 year / National Academy of Agrarian Sciences of Ukraine ; National Agricultural Agricultural Library of NAAS ; The Council of Young Scientists of NAAS [and others]] ; compls. Verhunov, V. A., Bilotserkivska, A. S. and Davydenko, M. M. ; editorial board : Verhunov, V. A. (heard). Kyiv : TOV «Tsentr polihrafii «KOMPRYNT», pp. 24–28 [In Ukrainian].
6. Ferchuk, A. (2013). Zachynatel’ vynakhidnyts’koho rukhu v Ukrayini Yuriy Lanhe [Yuriy Lange, the founder of the inventive movement in Ukraine]. Doslidzhennya z istoriyi tekhniky − Research on the history of technology, issue 18, pp. 48−52 [In Russian].
7. (1929). Predislovie [Preface]. Tsentralnii derzhavnii іstorichnii arkhіv Ukraini, m. Kyyv − Central State Historical Archive of Ukraine, Kyiv city, f. 2211 «Yuriy Valentinovych Lange − hydrotechnical engineer and teacher», op. 1 (1903−1929), 40 ark. [In Russian].
8. (1917). Vremennaya instruktsiya Kruzhka izobretatelei pri Kievskom politekhnicheskom obshchestva inzhenerov i agronomov [Temporary instruction Circle of inventors at the Kyiv Polytechnic Society of Engineers and Agronomists]. Byulleteni Kievskogo politekhnicheskogo obshchestva inzhenerov i agronomov − Bulletins of the Kyiv Polytechnic Society of Engineers and Agronomists, no. 1, pp. 8–10 [In Russian].
9. (1917). Otchyot o deyatelnosti podsektsii Kievskogo politekhnicheskogo obshchestva inzhenerov i agronomov «Kruzhok izobretatelei-lyubitelei» [Report on the activities of the subsection of the Kyiv Polytechnic Society of Engineers and Agronomists «Club of Inventors-Amateurs»]. Byulleteni Kievskogo politekhnicheskogo obshchestva inzhenerov i agronomov − Bulletins of the Kyiv Polytechnic Society of Engineers and Agronomists, no. 1, pp. 5–6 [In Russian].
10. (1917). Izvlechenie iz protokolov o deyatelnosti Kruzhka izobretatelei [Extract from the protocols on the activities of the Circle of Inventors]. Byulleteni Kievskogo politekhnicheskogo obshchestva inzhenerov i agronomov − Bulletins of the Kyiv Polytechnic Society of Engineers and Agronomists, no. 1, pp. 6–7 [In Russian].