WILD LEVELS FOR EVERY LEVELING TASK
Heerbrugg Ltd. Heerbrugg Switzerland printed in 1965)
Each Wild level has been designed for a particular
field of application and with a definite type of user in mind. The range extends
from the simple dumpy level, used by the builder or farmer for construction or
drainage tasks, to the precision level for the civil engineer or geodetic
surveyor who requires the highest possible accuracy. All Wild levels have
powerful telescopes, commensurate with their required function, with coated
optics, internal focusing-and stadia lines for distance measurement. The initial
rapid pre-leveling is made with the aid of a circular bubble and three foot screws,
which are protected against dust and which can be adjusted to ensure a smooth
and adequate run. In the ease of the Wild NA2 Automatic Engineers' Level, the
circular bubble has merely to be centered carefully to make the line of sight
horizontal. All knobs are controlled, and all eyepieces are viewed, without the
observer having to change his position. The NK01 has a metal horizontal circle
as a standard feature. With the exception of the N3, all other levels can be
supplied either with or without a glass horizontal circle, depending upon the
customers requirements. When a glass circle is fitted to a level the code
name has a "K added to it - e.g. NK10, NK2 and NAK2, respectively. In
all cases the glass circle of a "K level is read through the eyepiece of
a scale microscope. The main numbered divisions are in degrees or grades and the
auxiliary scale is in 10 minute intervals, with accurate estimation possible to
1/10 of each such interval.
The smaller Instruments (NK01, N10 and NK10) have a
shock-proof plastic container which is exceptionally strong and long lasting,
although very light and easy td handle.
other Wild levels are carried in metal containers, specially designed to give
the maximum protection in the simplest form.
Wild NK01 Dumpy level is a most convenient level for the building site. The
telescope rotates under a friction-braked action, thus requiring no horizontal
clamp. Fine pointing is completed by means of a tangent screw. Readings on the
metal horizontal circle are made by eye against a fixed index mark, with
estimation possible to a tenth of a degree or grade, according to the circle
division. The circle itself can be turned by hand to set any desired initial
bearing. The circular and tubular level bubbles are seen, free from parallax, in
the hinged observation mirror which, when closed, protects the glass vials.
The Wild N10 Small Engineers' Level is an efficient
compact and lightweight instrument, giving highly accurate results under all
conditions. It is suitable for general leveling, project studies, route surveys,
irrigation works, civil and constructional engineering. When fitted with a glass
circle (NK10) it can be used in flat terrain for tacheometric work and for
measuring or setting-out horizontal angles. The line of sight is leveled with
the aid of a tilting screw and the well known Wild "split-bubble"
image system. It has an extremely short minimum focusing distance of 1 meter
(3.3 feet), which is most useful.
lt is possible to supply this instrument with an
upright image telescope (models N10-E and NK10-E) - a feature often appreciated
by those who use their level only occasionally or who find it difficult to work
with an inverted image. The E-models have a minimum focusing distance of 1.35
meters (4-5 feet).
The Wild N2 Engineers Level is a strongly built,
accurate and reliable general purpose instrument, which is easy to operate. It
is unsurpassed foe use on civil and constructional engineering projects, bench
mark Establishment breaking down primary level networks, profiles,
cross-sections, road and railway surveys and for photogrammetric height control.
When fitted with a glass circle (NK2) it can be used in flat terrain for setting
out works and for measuring horizontal angles and distances. Fine pointing is
made with a horizontal clamp and a tangent screw and an accurate coincidence
setting of the tubular level split bubble image is made by means of a tilting
screw. The telescope and tubular level can rotate simultaneously about the
longitudinal axis, enabling the vertical collimation to be checked easily at one
Wild NA2 Automatic Engineers' Level is particularly useful when accurate
readings are required quickly. After the circular bubble has been centered
carefully, by means of the foot screws, the line of sight is made horizontal
automatically through the pendulum type compensator. As a result the NA2 has
neither a tubular level nor a tilting screw. Being insensitive to the sun no
umbrella is required and this also helps to speed up the leveling. A plane
parallel plate micrometer is now available as an optional accessory to the NA2
(and the NAK2, which is identical to the standard model, with the addition of a
glass horizontal circle) and this attachment enables an even higher accuracy to
be obtained. With it, direct readings to 0.001 ft. or 0.1 mm are made and
estimation to 0.0005 ft. or
0.01 mm is possible without difficulty. The micrometer eyepiece is placed most
conveniently just above the telescope eyepiece. The reticule differs from the
normal type, as one half of the horizontal line has been replaced by two
wedge-shaped lines, converging towards the center so that either the chess-board
type of staff or one with graduated lines may be used. The telescope gives a
bright, contrasting, upright image and the horizontal rotation is
friction-braked, with an endless tangent screw for fine pointing.
Wild N3 Precision Level is an outstanding instrument for all first order leveling
work. Designed originally for geodetic networks it has been adopted universally
as the ideal level for the precise measurement required in dam deformation
surveys, industrial installations, aircraft fuselage assemblies and vertical
displacement determinations. The plane parallel plate micrometer is mounted in
front of the objective lens as a built-in feature of the N3 and is available in
metric and non-metric models, giving reliable and simple estimation to 0.01 mm
and 0.0005 inch,
respectively. The reticule has part of its-horizontal line in the form of two
wedge-shaped lines, converging towards the center allowing the staff graduation
to be split or straddled, depending on the circumstances and on which part of
the cross-hair is used. Collimation errors are corrected by means of a rotation
of the objective lens cover glass which enables an exceptionally sensitive, but
simple, adjustment to be made. Interchangeable eyepieces provide the possibility
of observing with either an inverted or an upright image.
Technical Data of Wild Levels (1965) TOP
Technical Data of Wild Levels (1981) TOP
All "K model levels have a 360° or 400g horizontal circle. The N10 is
also supplied as the N10-E and NK10-E, with upright image. Apart from a shortest
focusing distance of 1.35 m (4.4 feet) the data for these E models are the same
as for the N10 itself.
Wild staves are made in varying lengths and for all
possible purposes. For accurate leveling and all types of optical distance
measurement the graduations on the staves are clearly marked and easy to read,
allowing the observer to use his instrument to the best advantage. Leveling
(NL), Topographical (TL) and Tachometry (VL) staves are all made with the care
and precision expected from Wild products. Folding in
the middle, each staff has strong hinges and reinforced backing for rigidity.
The handles enable the staff to be carried easily and in balance. Depending on
the model the staves are available with centimeter graduations (3,
4, 5 meters long) or with 0.01 ft. graduations (12 feet long). The NL and TL
staves are made with inverted numbering or up-right numbering (NLE and TLE models) and the VL
Tacheometric staves, which are available only with upright numbers, can also be
supplied with an extending leg, enabling the zero mark to be set at instrument
height. The illustration indicates a representative selection of the metric and
non-metric, upright and inverted, and "chess-board" and division
graduation types, respectively. All Wild staves have a detachable leveling
bubble to help the staff man to obtain correct verticality.
Wild NA2 and N3 levels, with plane parallel plate micrometers, require staves
with even more precision than is available in the highly accurate normal range
of NL, TL, and VL staves. For this reason the Wild PNL Invar Precision Leveling
Staves are available, 3
meters in length
and with either inverted or upright (PNL-E) images. The invar facing inset into
each staff has two 'sets of graduated divisions. The divisions down one side of
the facing indicate the correct height (in centimeters) above the base of the
staff, whilst the divisions down the other side are displaced by a small amount
and are also numbered with an added constant. By reading to each set of
graduations an , immediate check against gross errors is obtained. The invar is
held under constant, standard tension by means of a spring at the upper end and,
because of this and the extremely low coefficient of thermal expansion of invar,
there is negligible change of interval between divisions. When working in areas
where large differences in height are being measured under conditions of large
temperature changes it is possible to make accurate corrections to compensate
for the effect of differential expansion. When using an invar staff it should
always be set up on an iron ground plate, and, as an additional safeguard, the
Wild detachable struts should also be used. Verticality is ensured with the aid
of the detachable leveling bubble.
industrial use special WL Industrial Staves are available, made with invar and
92 cm, 182 cm, 36 inches
and 72 inches long, respectively.
Swiss Precision and Expert Craftsmanship are
world-renowned, the excellence and fame of the Swiss watch making industry being
a perfect example of this justified reputation. All Wild instruments and
accessories are made with the same traditional skill and exactness and for this
reason Wild quality is equally famous. The checking system at all stages of the
manufacturing sequence ensures that only the highest quality equipment is
allowed to be placed on the market.
In addition to the normal tests every instrument is
subjected to exposure in a temperature controlled chamber, where careful
readings are made throughout the range from 50°
to +50° Centigrade (-58° to +122° Fahrenheit), and also to vigorous shaking on
a special vibration machine.
Proof of the popularity enjoyed by Wild is the fact
that more than 30.000 T1A repetition theodolites and T2 Universal theodolites
are now in use throughout the world.
All tripods have a standard fixing screw and a similarly shaped head, enabling any Wild level or theodolite. (and also the full range of accessories designed to be mounted on a tripod, as opposed to those for attachment to an instrument) to set up on any Wild tripod. Although each instrument has a particular tripod recommended for its use, it is possible, if circumstances demand, to make use of any Wild tripod that happens to be available. It is, of course, not advisable to use a large instrument on a tripod with a head that is much too small but, in an emergency, it could be done. All tripods have a pouch containing accessories and in most eases they are available with either rigid or telescopic legs (types a and b, respectively). With the exception of the metallic 16bL, they are made from carefully selected and well seasoned wood.