Rabbi Yechiel Michel Tucazinsky (1872-1955) is best known for (and referred to as the) Gesher HaChaim
Although best known for Gesher HaChaim and described as "one of the premier authorities on the Laws of Mourning", another cited work is his Hayomam BeKadur Ha'aretz, regarding The International Dateline in Jewish Law.
Rav Tucazinsky initiated the annual "Luach Eretz Yisrael" calendar in 1904,and also authored:
Born in Lithuania, at age 8, after the passing of his father, he immigrated to Israel, where he studied in and later headed the Etz Chaim yeshiva, later run for "over fifty years" by his (late) son HaRav Nissan Aharon Tucazinsky. His wife was a great-granddaughter of Rabbi Shmuel Salant.
mashgiach of Slabodka in Bnai Brak, and founder of Yeshivas Mekor Chaim in Yerushalayim. In 1925, he published a sefer called Tekufas Hachamoh Uvirchosoh, in preparation for the bracha made when the sun returns to the point at which it began upon Creation. He wrote a sefer called Bein Hashmoshos, published in 1929, which dealt with the International Date Line. In 1941, he changed his mind altogether, as documented in his sefer, Hayomam Bekadur Haaretz, in which he shows that the new day begins 12 hours to the east of Yerushalayim. His kever is in Haditch, Ukraine.
May the merit of the tzadik Rabbi Yechiel Michel Tucazinsky protect us all. Amen