  We use high temperature series expansions to study the $\pm J$ Ising
spin-glass in a magnetic field in $d$-dimensional hypercubic lattices for $d=5,
6, 7$ and $8$, and in the infinite-range Sherrington-Kirkpatrick (SK) model.
The expansions are obtained in the variable $w=\tanh^2{J/T}$ for arbitrary
values of $u=\tanh^2{h/T}$ complete to order $w^{10}$. We find that the scaling
dimension $\Delta$ associated with the ordering-field $h^2$ equals $2$ in the
SK model and for $d\ge 6$. However, in agreement with the work of Fisher and
Sompolinsky, there is a violation of scaling in a finite field, leading to an
anomalous $h$-$T$ dependence of the Almeida-Thouless (AT) line in high
dimensions, while scaling is restored as $d \to 6$. Within the convergence of
our series analysis, we present evidence supporting an AT line in $d\ge 6$. In
$d=5$, the exponents $\gamma$ and $\Delta$ are substantially larger than
mean-field values, but we do not see clear evidence for the AT line in $d=5$.
