Bulk sintered and powdered samples of the high-temperature superconductive compounds ${\mathrm{Tl}}_{2}$${\mathrm{Ca}}_{2}$${\mathrm{Ba}}_{2}$${\mathrm{Cu}}_{3}$${\mathrm{O}}_{1+\mathrm{\ensuremath{\delta}}}$ (Tl-2:2:2:3) and ${\mathrm{Tl}}_{2}$${\mathrm{Ca}}_{2}$${\mathrm{Ba}}_{2}$${\mathrm{Cu}}_{2}$${\mathrm{O}}_{8+\mathrm{\ensuremath{\delta}}}$ (Tl-2:1:2:2) have been synthesized with phase purity of approximately 90%. The materials were characterized by x-ray-diffraction, metallographic, and electron microprobe analyses. The electronic and superconductive properties were investigated through measurement of the electrical resistivity and the critical current density ${J}_{c}$ using transport methods and by extensive magnetization measurements. Primary results and conclusions are that (1) the intragrain ${J}_{c}$ values were large, much larger than the transport values; (2) both sintered and powdered materials exhibited large flux creep; (3) and the ${J}_{c}$ decreased exponentially with temperature. These features are qualitatively very similar to those found in the corresponding ${\mathrm{YBa}}_{2}$${\mathrm{Cu}}_{3}$${\mathrm{O}}_{\mathrm{z}}$ (with z\ensuremath{\approxeq}7) series of compounds.