A modified Frantz separator was used for a single wire longitudinal hgms study to test two suggestions regarding downstream capture: (i) it follows the loading equation (Nesset et al [4], and (ii) it is favoured in the stationary wake (

) and for

(Watson [5]). Suggestion (ii) is supported. Nevertheless, a regular matrix follows the loading equation, indicating that single wire results may be difficult to extrapolate to a matrix.