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Thesis
The key words in “其水用山水上江水中井水下其山水拣乳泉石池漫流” are not ornament. They mark where Tang tea names, vessels and provenance meet.
Text
“For water, mountain spring is best, river next, well lowest. Of mountain springs, choose the milky fountains that seep from rocky pools; avoid rushing, churning torrents.”
Context
乳泉：石乳般的泉水。石池漫流：从石池缓缓流出的水。瀑涌湍漱：奔涌湍急的水。
Evidence
- Collation: 此句为五之煮名句，各本一致。吴觉农注："乳泉石池漫流"指流速和缓、杂质沉淀后的活水。
- Existing readings: 吴觉农指出"瀑涌湍漱勿食"极有科学眼光：急流之水挟带泥沙与气泡，杂质多、口感糙；缓流石池水经砂石过滤更清冽——"静水流深"正合好水标准。
Analysis
The annotation matters less as philology than as a distinction between name and thing. 此句为五之煮名句，各本一致。吴觉农注："乳泉石池漫流"指流速和缓、杂质沉淀后的活水。 Once names settle, picking, grading and trade can share a language.
Conclusion
The section does not give a universal rule. It demonstrates a method: read the text, the annotation and the Tang context together before making a modern claim.
Source: The Classic of Tea, Chapter IV · The Vessels, section 6; the original is in the public domain.
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