Interplanetary scintillation (IPS) can be used to identify changes in
solar wind parameters over a wide range in heliographic latitude and e
longation and constrain models of its large-scale structure, velocity
and density. this paper reviews the scintillation density mapping meth
od specifically, and presents over three years of data taken between M
arch 1990 and September 1993 with the 3.6 hectare array in Cambridge.
A novel form of synoptic plot that is particularly sensitive to corota
ting structures is introduced, and low-density streams are identified
by their unequivocal signatures within it. Stable corotating structure
s are evident throughout - even during the active phase of the solar-c
ycle - and specific periods are examined. Density measurements inferre
d from scintillation are compared with IMP-8 data for the same period
and are shown to be in good agreement, giving further support to the s
cintillation/density relationship determined by Tappin (1986).