Responsa for Bava Kamma 230:10
דעבר לה במסננת כר' נחמיה דתניא מסננת יש בה משום גילוי אמר רבי נחמיה אימתי בזמן שהתחתונה מגולה אבל בזמן שהתחתונה מכוסה אף על פי שהעליונה מגולה אין בה משום גילוי לפי שארס של נחש דומה לספוג וצף ועומד במקומו
This is a sufficient reason in the case where the barrel broke, as [the wine remaining] is still fit to be used, but in the case where the barrel became uncovered, for what use is the wine fit any more? For should you argue that<span class="x" onmousemove="('comment',' Though it is no more good as a drink. ');"><sup>25</sup></span> it is still fit for sprinkling purposes, was it not taught: Water which became uncovered should not even be poured out on public ground, and should neither be used for stamping clay, nor for sprinkling the house,<span class="x" onmousemove="('comment',' For the venom which it might contain might injure persons walking there barefooted. ');"><sup>26</sup></span> nor for feeding either one's own animal or the animal of a neighbour?<span class="x" onmousemove="('comment',' Tosef Ter. XVII, and A.Z. 30b. ');"><sup>27</sup></span>
Teshuvot Maharam
A. Since the books were taken by Gentile robbers, A did not lose hope of retrieving them (B. K. 114a) and thus legally retained title to his books. Therefore, B must return the books to A. B is not entitled to any compensation, since it was common knowledge that A was robbed of his books, and since B bought them from known robbers.
This Responsum is addressed to "my teacher Rabbi Eliakim."
SOURCES: Pr. 1009; Cr. 196–7; Mord. B. K. 163.
Teshuvot Maharam
A. A is under no obligation to return the book to its owners, for as soon as the latter gave up hope of saving the book, it became abandoned property.
SOURCES: Cr. 251; Mord. B. K. 171; Mordecai Hagadol p. 392d; Hag. Maim., Gezelah 12, 6; Agudah B. K. 140.
Teshuvot Maharam
A. A dowry gift becomes the property of the donee only if the marriage takes place. Therefore, neither A nor his daughter has ever gained title to B's money, and A must return the principal plus the interest to B. Even if B expressly stipulated that he will forfeit the 15 pounds if the marriage does not take place, such a stipulation is considered an Asmakhta and is not valid. B, however, must pay A for his trouble in managing B's investments.
SOURCES: Cr. 86; Pr. 285; Mord. B.B. 615; Agudah B.B. 198.