Studies on water movements and sediments in Southern Lake Michigan : part 1[-3] ... / by John C. Ayers.

obtained. Mean components were computed from the mean slopes
of the surface;slopes along the ships' tracks being averaged
and slopes transverse to the tracks being averaged. The two
components thus obtained for each "square"f were summed
vectorially to produce the current vector that is drawn from
the midpoint of each "square."
Isotherms of 150 and 160C are entered in the figure in the
places where they were encountered by the two ships.
In the last ten miles of the short converging leg of the
crossing, only the current components normal to the ships'
tracks were computed. The averages of these are shown as
dashed arrows.
The wind regime under which these crossings were made was:
22 Oct. S 20-25 knots
23 Oct. S 12 k (diminishing during night)
Although the 2-mile spacing between the ships9 tracks is
too small to delineate clearly the nature of the current
structure, it is sufficient to suggest that eddies of different sizes and of both right-hand and left-hand rotation were
present and probably moving within an overall drift. Single
transects across such a structure would produce the appearance
of "streaks" of oppositely directed current as reported in
Part I.
Tests of Wind Effects on DroEues
Test of 9-10 October 1963 (Old Floats,, Old Drags The
old-style drogue floats consisted of a styrafoam float 16-1/2
inches square and six inches deep. Through the center of the
styrafoam there was a 10-foot aluminum pipe of 5/8th inch

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