Treaties — Special kinds of — Double taxation conventions — Income-Tax Convention between United Kingdom and United States, 1945 — Interpretation of — Whether exemption benefits under Convention extend to resident of United Kingdom who is beneficiary of trust under United States law — Whether trust with British beneficiaries taxable for capital gains — Normal usage of words — Purpose of Convention — The law of the United States of America.

Treaties — Interpretation of — Principles and rules of interpretation — United States-United Kingdom Income Tax Convention, 1945 — Whether exemption benefits under Convention extend to resident of United Kingdom who is beneficiary of trust created under United States law — Whether trust with British beneficiaries taxable for capital gains — Normal word usage — Purpose of Convention — The law of the United States of America.