When no allowance is made in this act for clerical hire in any of the county offices herein provided, then the board of county commissioners shall allow such additional amount for clerical hire as may be necessary to properly expedite the business of said offices. When, in the opinion of the county commissioners, the amount of the allowance made in this act for clerical hire shall be insufficient to properly and sufficiently conduct the business of said office, then the board of county commissioners shall allow such additional amount of clerical hire as may be necessary to properly expedite the business of said office, but not exceeding, however, ten percent of the allowance herein provided: Provided, That no allowance shall be made except by resolution of the board of county commissioners made in regular session convened, setting out the reason for the said allowance as made, and the amount of the allowance: And provided further, That no allowance shall be made for more than a six months period and shall not be effective until said resolution shall have been entered upon the journal and shall have been published once in a paper of general circulation in the county and no warrants shall be issued for such additional clerk hire for any period prior to the date of said publication.