Bava Batra

If he says 'my property',  this would include houses and slaves also. If the seller draws one of two parallel boundaries shorter than the other, Rab says that the purchaser obtains only the width of the shorter line.  R. Kahana and R. Assi said to Rab: Should he not obtain as much as is bounded by the oblique line?  — Rab made no reply.  Rab, however, had [previously] admitted that if [the field in question] is bounded by those of Reuben and Simeon on one side, and by those of Levi and Judah on the other, since [if he desired to transfer only half the field] he should have written either '[the boundaries are the field] of Reuben [on one side and] opposite [to it the field of] Levi', or else '[the field] of Simeon [on one side and] opposite [to it the field of] Judah', and he did not do so, he meant to transfer all within the oblique line [from the end of Simeon's field to the end of Levi's]. If the field is bounded by fields of Reuben on the east and west and by fields of Simeon on the north and south, he must write, 'the field is bounded by fields of Reuben on two sides and by fields of Simeon on two sides.' The question was raised: If he merely marks the corners,  how do we decide? If he draws the boundaries like a gam,  how do we decide?