and by means of a bill of sale.

The Gemara clarifies the baraita: Letters in promissory notes, who mentioned anything about them? Why would Rabbi Natan speak about promissory notes, which are not discussed by the first tanna? The Gemara answers: The baraita is incomplete, and this is what it is teaching: A ship is acquired by pulling, and letters, i.e., the content of a promissory note, are acquired by merely transferring the document, not through pulling. Rabbi Natan says: A ship and letters are acquired by pulling and also by means of a bill of sale.

The Gemara asks: Why do I need a bill of sale for a ship? A ship is movable property, which is acquired not by means of giving a bill of sale, but through other acts of acquisition. Rather, is it not correct to say that this is what the baraita is teaching: A ship is acquired by pulling, and letters of credit by passing. Rabbi Natan says: A ship is acquired by pulling, and letters, i.e. the contents of a promissory note, are acquired either through pulling or by means of a bill of sale.

The Gemara asks: If Rabbi Natan holds that a ship is acquired by pulling, his opinion is apparently identical to the opinion of the first tanna. Rather, the practical difference between the two opinions is the dispute of Rav and Shmuel. According to the opinion of one tanna the buyer must move the entire ship out of its current location, while the other tanna maintains that one must move the ship only a minimal amount. The Gemara rejects this suggestion: No, everyone, Rabbi Natan and the first tanna, holds either in accordance with the opinion of Rav, or in accordance with the opinion of Shmuel. And with regard to a ship, everyone agrees that it is acquired through pulling.

When they disagree, it is with regard to acquiring letters, i.e. the contents of a promissory note. And this is what Rabbi Natan is saying to the first tanna: With regard to a ship, I certainly concede to you that it is acquired by pulling. But with regard to letters, whereas you maintain that passing suffices to acquire them, I hold that if in addition there is a bill of sale, yes, the acquisition is valid, but if not, the act of passing is not effective.

And according to this interpretation, the first tanna and Rabbi Natan disagree with regard to the dispute between these tanna’im. As it is taught in a baraita: Letters, i.e., the contents of a promissory note, are acquired by merely transferring the document; this is the statement of Rabbi Yehuda HaNasi. And the Rabbis say: Whether one wrote a bill of sale but did not transfer the promissory note to the buyer, or whether he transferred the promissory note but did not write a bill of sale, the buyer does not acquire the documents until the seller both writes a bill of sale and transfers the promissory note.

The Gemara asks: In accordance with which opinion did you interpret the opinion of the first tanna of the aforementioned baraita? If it is in accordance with the opinion of Rabbi Yehuda HaNasi, then let a ship be acquired also by passing, not only through pulling, as stated in the following baraita. As it is taught in a baraita: A ship is acquired by passing; this is the statement of Rabbi Yehuda HaNasi. And the Rabbis say: The buyer does not acquire it