It is unclear whether the "this," here, refers back to 1:01, forward to what he is about to say, or something else. In the absence of further information, 湯 tāng presumably refers to King Tang, founder of the Shang Dynasty. Commentators explain the term as meaning "broad" here (possibly in connection with its cognate 蕩 dàng, "vast") in contrast to the name of the otherwise unknown and probably fictional character 棘 Jí, which means "thorns," or, by extension, a narrow, uncomfortable place, hence "Cramped."
Burton Watson in The Complete Works of Chuang Tzu (Columbia UP: 1986, p. 31) cites a quotation in a Tang Dynasty Buddhist text, 北山錄 běishān lù, said to have come from Zhuangzi: "Tang asked Cramped, 'Do up, down, and the four directions have a limit?' Cramped replied, 'Beyond their limitlessness there is still another limitlessness.'" But those lines are not present in any extant editions of Zhuangzi. A later text, 列子 Lièzǐ, contains a chapter titled "The questions of Tang," which contains similar inquiries into limits of space and time and even mentions Dark Spirit and Big Spring (Liezi Tangwen and Graham 1960: 94 ff.). It is possible that the Liezi chapter was based on Zhuangzi or that they were both based on some unrecorded folklore, or simply made up.