The gemara left with Teiku regarding a nut in a cup on the water. But the mishna on amud bet says that if one throws onto a ship (in the water), he is patur. why cant we be poshet the first shaila from the mishna?
Yaakov Siegel, miami, florida
Tosfos (5b, DH "Egoz") explains that although a boat is definitely considered "Nach," a cup is definitely not Nach. He explains that Rava's question is whether or not it is normal for one to put his items into a vessel on the water, and therefore akin to the manner in which they did Hotza'ah in the Mishkan, when they would transfer their objects from one domain into another. Accordingly, the question does not have to do with the Mishna regarding the ship (100b). [Note: this answer is not according to all Rishonim (i.e. those who learn Tzricha l'Gufa differently than Tosfos).]
All the best,
I don't think Tosfos is referring to a Tziricha L'gufa Din. It's rather a Din in what's concidered moving or settled. Thus the requirement to be considered settled to make a Hanacha is the same requirement of how they put down objects in the Midbar. Learning the particulars of the Malachos from the Mishkan are universal regardless of how you learn Tzricha L'gufa or if you don't hold of it at all.
After reviewing this further, I agree that the remark in the brackets referring to Tzricha l'Gufa does not seem accurate. Thank you for pointing this out.