(1) The dying declarations of a deceased person are admissible in evidence in all civil and criminal trials and other proceedings before courts, commissions, and other tribunals to the same extent and for the same purposes that they might have been admissible had the deceased survived and been sworn as a witness in the proceedings, under the following restrictions. To render the declarations of the deceased competent evidence, it must be satisfactorily proved:
(a) That at the time of the making of such declaration he was conscious of approaching death and believed there was no hope of recovery;
(b) That such declaration was voluntarily made, and not through the persuasion of any person;
(c) That such declaration was not made in answer to interrogatories calculated to lead the deceased to make any particular statement;
(d) That he was of sound mind at the time of making the declaration.