File Name : si_fig1.eps

Caption : measured enhancement of friction indued by cohesion (same data as in figure 2a of the paper, obtained for a fixed softness k = 10−3). main: μ/μd = g as a function of the cohesion strength c (symbols: numerical results; line: linear fit by eq (5). inset: slope a = ∂g/∂c as a function of the inertial number (red line fitted by a=bk^(1/2)/(i+i1)).