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MISCELLANEOUS NOTES

THE BOOMERANG.
The proper Aboriginal name of the instrument is Tur-rur-ma, miscalled by the English, originally, in this
Colony Boomering:- then in England Boomereng and now finally settled Boomerang by the Colonial
press - The original name Boomering is generally applied to the instrument by the colonists and by several
of the Aboriginal tribes in the interior

[sketch of 2 types of propellers]

BRIEF OBSERVATIONS ON THE BOOMERANG PROPELLER BY THE HON. THE EARL OF DUNDONALD
To comprehend the extrordinary properties of this Propeller, it is necessary to consider the effect produced on
water by the commom propeller, fitted with two opposite arms at right angles to the shaft having blades,
which repel the fluid in the form of a cone.

[sketch of a propeller]

To obviate this divergence, a propeller with oblique arms and curved blades was suggested, and favourable
notice of its principle made in scientific works -

[sketch of a propeller]

Without entering into detail, the Boomerang propeller combines advantages which neither the diverging,
nor the direct linesd of propulsion, singly possess -

[sketch of a boomerang propeller]

One blade of the Boomerang A causes the water to recede in a cylindrical spiral; the other,
B, in a revolving cone. The spiral describes a complete cylinder, therefore half its capacity becomes
occupied by quiescent water, whilst the centrifugal cone abuts successively, & continuously, on the
same medium - perhaps more advantageously on a counter current, produced by the more rapid
recession of the central stream. It is superfluous to add that the water of propulsion, thus
retarded re-acts on the propelling power, enabling the Boomerang Propeller to approximate the
properties of a screw, forced into a solid substance

Signed Dundonald.

29th August 1853_