$c_1 x$, where $c_0$ and $c_1$ are approximately constant (apart from small confluent corrections $\propto L^{-\omega}$). For all data points in Fig. 6 we have $|x| < 0.18$ and the linear scaling with $(1-\beta/\beta_c)$ is obviously satisfied. Moreover, a closer look shows that also the scaling with $L^{1/\nu}$ is very well confirmed (using our estimate of $\nu = 0.704$ the deviations from the straight line fit of the curves at $\beta \ne \beta_c$ for $L=32,40$ and $48$ should be stronger than those for $L=24$ by factors of about 1.5, 2.1 and 2.7, respectively). In fact, in a scaling plot all curves would fall on top of each other. The theoretical predictions for $\eta$ are 0.040(3) (resummed $\epsilon$-expansion) and 0.033(4) (resummed perturbation series), and inserting (\[eq:18d\]) in the scaling relation $\eta = 2\beta/\nu -1$ gives $\eta = 0.028(2)$. Our direct estimates of $\eta$ for $\beta=0.6930 \pm 0.0001$ are collected in Table 2. It is also interesting to note that $\eta$ gets closer to the theoretical values for $\beta<\beta_c$ for $\chi$, and for $\beta>\beta_c$ for $\chi^{\rm c}$, hence just in the regions in which both expressions are naturally used. Another check on $\eta$ can be obtained from the maxima of $\chi^{\rm c}$, 