Derech Chaim VeTochachat Mussar Haskel - Shaar HaTeshuvah and Shaar HaTefillah, by Rebbe Dov Ber, the Mitteler Rebbe of Lubavitch. [Kopust/Russia? 1819?]. Title page states: "in Kopust".
This edition is recorded as a third variant of the Kopust 1819 edition, However, Habermann writes that it was printed in Lviv, ca. 1850. R. Shalom Dov Ber Levine maintains that it was printed in a clandestine Chabad printing firm in Russia at the time the printing of Hebrew books was outlawed (1837 onwards).
[4], 60, 65-136 leaves. Lacking 4 leaves: 61-64. 18.5 cm. Fair-good condition. Stains, including dampstains and dark stains. Wear. Tear to title page and minor tears to another leaf, repaired with paper. Minor worming. Stamps and handwritten inscriptions. New leather binding.
Stefansky Chassidut, no. 138.

Rebbe Dov Ber Shneuri (1774-1828), known as the Mitteler Rebbe of Lubavitch, was the son of R. Shneur Zalman of Liadi, the Baal HaTanya. After his father passed away (December 1812) while fleeing the French invasion of Russia, he began serving as rabbi in Lubavitch (Lyubavichi). In his father's lifetime, he recorded the latter's teachings, and delivered public lectures based on them, even in his presence, with the addition of his own commentaries. He was gifted with brilliant profundity and an unlimited wellspring of Torah thoughts. His Chassidic discourses would extend over many hours. He had an exceptional talent for clear explanations, whether in writing or orally, and was able to clarify and simplify before laymen the most profound and abstract concepts in Kabbalah and Chassidut. He was endowed with a rare ability to concentrate, and was able to contemplate G-dly concepts for hours on end, completely unaware of his surroundings. The Lubavitcher Rebbe retold that on Yom Kippur, he would stand in his place the entire day, in devoted prayer detached from physicality, without budging, with sweat pouring from his head. He passed away whilst delivering a Chassidic discourse.