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A. NELSON-SMITH
FIG. 3. A pneumatic boom (" bubble barrier ") retaining burning oil in the harbour at
Ghent (Belgium) ; note that the wind is blowing the oil towards but not across the
barrier, which is partly obscured by reflected sunlight at lower right (photo:
Rudolf Harmstorf Lt,d.).
" pneumatic barrier " (Stehr, 1959, 1964; Abbott, 1961 ; Sorrentino,
1963) in which a perforated pipe remains permanently on the bottom.
When required, compressed air is fed into it, producing bubbles which
lift a current of water to form a standing wave on the surface. This
entrained water, flowing away on each side of the line of bubbles,
prevents the drift of oil and other floating debris quite effectively without hindering the passage of shipping (Fig. 3).
I n a dock where oil is spilt regularly and can be boomed, it is usually
A. NELSON-SMITH
FIG. 3. A pneumatic boom (" bubble barrier ") retaining burning oil in the harbour at
Ghent (Belgium) ; note that the wind is blowing the oil towards but not across the
barrier, which is partly obscured by reflected sunlight at lower right (photo:
Rudolf Harmstorf Lt,d.).
" pneumatic barrier " (Stehr, 1959, 1964; Abbott, 1961 ; Sorrentino,
1963) in which a perforated pipe remains permanently on the bottom.
When required, compressed air is fed into it, producing bubbles which
lift a current of water to form a standing wave on the surface. This
entrained water, flowing away on each side of the line of bubbles,
prevents the drift of oil and other floating debris quite effectively without hindering the passage of shipping (Fig. 3).
I n a dock where oil is spilt regularly and can be boomed, it is usually