I. No public expressions of Aveilus are manifested on the actual ninth of Av because it is Shabbos. One may eat and drink on this Shabbos as one would on any other Shabbos. Nevertheless, some restrictions do still apply on this Shabbos.

1. Devarim Shebizinah, pleasurable activities done in private, such as marital relations, are prohibited, unless Friday night is the night of Tevilah
   (Orach Chaim 555:19 Ramah, Magen Avraham sif katan 20; Mishna Brurah sif katan 40)

2. One should avoid taking strolls or pleasurable walks.
   (Shaarei Teshuvah 553 sif katan 5)

3. One should learn only those areas of Talmud Torah whch may be learned on Tisha B'Av. This applies, according to many, on Shabbos afternoon; some say it applies all day. On may, however, learn the Parshas HaShavua.
   (Magen Avraham 553 sif katan 7; Mishnah Brurah sif katan 9,10; Rama 554:4; Magen Avraham sif katan 7)

4. One may eat a full meal for Shalosh Seudos (i.e. the laws of Seudah HaMafsekes do not apply). However, one should not eat this meal with friends unless one always is accustomed to doing so. The meal must be completed by sunset, which is approximately 8:20 P.M.
   (Orach Chaim 555:10; Magen Avraham sif katan 14; Mishnah Brurah sif katan 23)

II. Because the observance of Tisha B'Av immediately follows Shabbos, certain other halachos become relevant.

1. One removes one's leather footwear (without touching them) after the recitation of Bor'chu, except for the chazan who does so beforehand. It is preferable to bring on's non-leather footwear on Erev Shabbos to wherever one will be on Motzaei Shabbos.
   (Ramah 553:2; see Mishnah Brurah sif katan 7)

2. Havdalah (on a Kos) is not recited this night. Only the bracha of Borei Meorei HaAish is said,preferable before the reading of Eichah.
   (Orach Chaim 556:1; Taz sif katan 1; Mishnah Brurah sif katan 1)

3. The rest of Havdalah, excluding the introductory psukim and the bracha on the besamim, is said on Sunday night; before saying this one should not eat or drink.
   (Orach Chaim 556:1)

4. A choleh who must eat on Saturday night or Sunday should first recite Havdalah over tea, coffee or juice (but not wine or grape juice).
   (Shaarei Teshuvah 556 sif katan 1; Kaf HaChaim sif katan 9)

5. One should not eat meat or drink wine on Sunday night, but all other restrictions of the Nine Days are lifted immediately after the fast.
   (Ramah 558:1; Shaarei Teshuvah sif katan 4; Mishnah Brurah sif katan 4)

Please feel free to contact Rabbi Taubes with any questions about the fast.