SOME NEW MECHANICAL DEVICES FOR OCEANOGRAPHIC RESEARCH 
by SHALE J. NISKIN 
Institute of Marine Science 
University of Miami 
Miami, Florida 
ABSTRACT 
The areas of principal oceanographic 
interest to the Institute of Marine Science 
of the University of Miami are the Straits of 
Florida, the Bahama Banks, Florida Bay and the 
Caribbean. The field problems arising in these 
areas of research, coupled with the specific 
requirements of the various departments at the 
Institute, has prompted the development of 
several new oceanographic tools. Three simple, 
inexpensive mechanical devices are described 
in this paper: a stabilized oceanographic 
reference marker buoy; a sterile biological 
sampler; and a hydrographic wire slope and 
azimuth indicator. 
OCEANOGRAPHIC MARKER BUOY 
INTRODUCTION 
Intensive studies are conducted by the 
Department of Physical Oceanography of current 
patterns in the Florida Bay area (1. Koczy,F.F. 
et al., 1959). The movements of current drift 
drogues are plotted with ship's radar relative 
to moored reference markers equipped with 
radar reflectors. As the drogue drifts out of 
radar range of the reference marker, another 
such marker is launched and anchored, the 
original marker being recovered later. Employ- 
ing these methods, continuous tracking of 
drogues for extended periods of time has been 
made possible. 
THEORY OF OPERATION 
In order to assure maximum range and 
detection, the marker buoy mast supporting 
the radar reflector must possess a high degree 
of vertical stability. Because of the deli- 
cate construction of the radar reflector, the 
mast must be free from sudden and violent 
movements, regardless of the state of the sea. 
The markers should be relatively light in 
weight to facilitate launching and recovery. 
However, types of marker buoys available in 
the past have been either too cumbersome or 
have not offered the desired degree of 
vertical stability. 
"Superior numbers refer to similarly numbered 
references at the end of this paper." 
246 
DESIGN The reference marker buoy subsequently 
designed to satisfy the requirements discussed 
in the preceding paragraph consists of a 
ballasted mast, its metacenter located below 
the surface of the water and positioned at the 
center of a buoyant flexible ring by spokes 
radiating from the mast to the buoyant ring. 
Wave-induced movements of the buoyant ring are 
not transferred to the mast, excepting some 
degree of vertical acceleration, which is 
considerably dampened by the spokes and the 
flexible nature of the ring. A mooring line 
is attached to the buoyant ring and, therefore, 
has only slight effect on the stability of the 
mast. Because of its peripheral point of 
attachment, the mooring line is not likely to 
foul on the submerged portion of the mast. 
In detail, (see Fig. 1) the buoyant ring 
consists of a length of polyethylene pipe 
coiled into a ring seven or eight feet in 
diameter, its ends coupled together and 
sealed. Nylon spokes radiating from a metal 
hub which is milled to receive the mast are 
secured to the buoyant ring. These spoke 
lashings also hold the ring coils together. 
One-third of the mast length extends below the 
central hub. Ballast is secured to the mast 
heel. The mast is prevented from slipping 
through the hub by a taped serving, which is 
applied to the mast. To meet our specific 
requirements, a radar reflector was secured 
to the top of the mast. 
HYDROGRAPHIC WIRE SLOPE AND AZIMUTH INDICATOR 
INTRODUCTION 
Hydrographic wire configurations produced 
by a combination of the Gulf Stream current 
and vessel drift in the Straits of Florida 
tend to complicate hydrographic instrument 
positioning. The usual technique of employ- 
ing unprotected thermometers for determining 
instrument location has not proven adequate 
for the task. A knowledge of wire slope and 
set can be useful for defining location of 
instruments attached to the hydro-wire. 
Furthermore, this information may yield indi- 
cations of sub-surface currents and their 
direction. 
