Section 1. Paragraph one hundred and seventy-seven of section eight of the Philippine Tariff Law, Act of Congress of August fifth, nineteen hundred and nine, is hereby amended to read as follows:
"177. Boots and shoes:
"(a) Of rubber, vegetable fibers, and canvas, pair, thirty-five cents.
"(b) Of cowhide, horsehide, sheepskin, and pigskin, and imitation thereof, pair, fifty cents.
"(c) Other, including shoes made of reptile skins, and slippers and sandals of whatever materials, except silk, pair, seventy-five cents.
"(d) The same, of silk, rayon, and other synthetic textiles, pair, one dollar. 1aшphi1
" Provided, That when any of the articles classified under clause (a) of this paragraph contain leather, skin, silk, or imitation thereof, in any proportion, they shall be dutiable under the corresponding clauses (b), (c), or (d) of this paragraph; and
" Provided, further , That no article classified under clauses (a), (b), (c), and (d) of this paragraph shall pay a less rate of duty than thirty, forty, forty-five, and fifty per centum ad valorem, respectively."