§ 39. Right to compensation. If an employee is disabled or dies and his disability or death is caused by one of the diseases mentioned in subdivision two of section three, and the disease is due to the nature of the corresponding employment as described in such subdivision in which such employee was engaged and was contracted therein, he or his dependents shall be entitled to compensation for the duration of his disablement or for his death in accordance with the provisions of articles two and three of this chapter, provided, however, that if it shall be determined that an employee so disabled is able to earn wages at another occupation which shall be neither unhealthful nor injurious, and such wages do not equal his full wages prior to the date of his disablement, the compensation payable shall be computed pursuant to the provisions of article two of this chapter.