In the postal administration sub-account the business of post, postal-money-order, postal savings and postal book transfer savings, the services concerning post office insurance and post office annuity, the business concening payment of annuity and pension, receipts and payment of other troasury fund and sale of revenue-stamps and transaction tax-stamps and the business incidental there to under the provision of Article 1, Paragraph 2 shall be managed, and in the telecommunication sub-account the business concerning telegraph and telephone, examination and research in the electoro-laboratory and the business incidental thereto under the said provision shall be managed.