Article 6. When it is desired that the official of the to, Hokkaido, or prefectures shall be made to engage in the aforesaid business, by the provisions of Article 5, paragraph 2 of the Law, the Governor of the to, Hokkaido, or prefectures to which the said official concerned belongs, is to choose and appoint such official from among those who are possessed of necessary knowledge and experience concerning the special contract.