There is hereby levied, assessed and shall be collected from each salesman, as defined herein, a tax of three percent (3%) of the gross amount of the orders taken where delivery is made to a consumer located in this state and when the merchandise is for consumption by the said customer.
Provided, however, that, in the case of the solicitation or taking of orders for merchandise from retailers for resale in the regular course of business, the tax shall be paid at the rate of one eighth of one percent (1/8 of 1%) of the total amount of such orders.