2. Do you remember the following words? Translate them into Ukrainian:

   tool – _____________________________ environment – ______________________ to draw – __________________________ to join – ___________________________ to invent – _________________________ ruler – ____________________________ to measure – _______________________ angle – ____________________________ to arrive – _________________________ straight – __________________________

   Earth – ____________________________ to create – _________________________ depiction – _________________________ cardinal – __________________________ difference – ________________________ to reach – __________________________ local – ____________________________ circle – ____________________________ nautical – __________________________ edge – ____________________________

3. Read and translate the following text:

Navigational instruments refer to the instruments used by nautical navigators and pilots as tools of their trade. The purpose of navigation is to ascertain the present position and to determine the speed, direction etc. to arrive at the port or point of destination.

Charts and drafting instruments

• Charts are maps of the areas to be navigated with details specific to the marine environment.

• Dividers used for measuring lengths of lines and approximate lengths of non-linear paths on a chart.

• Nautical almanac used to determine the position in the sky of a celestial body after a sight has been taken. A nautical almanac is a publication describing the positions of a selection of celestial bodies for the purpose of enabling navigators to use celestial navigation to determine the position of their ship while at sea.

• Parallel rules used for transferring a line to a parallel position. Also used to compare the orientation of a line to a magnetic or geographic orientation on a compass rose.

Parallel rulers are a drafting instrument used by navigators to draw parallel lines on charts. The tool consists of two straight edges joined by two arms which allow them to move closer or further away while always remaining parallel to each other.

History. The parallel ruler was invented in about 1584 by Fabrizio Mordente, but it was not in common use until the 18^th century. In the 19^th century, a Captain William Andrew Field (1796 – 1871) improved the design by adding a protractor-style scale to the upper edge of one rule, and compass points to the opposing edge, which made reading bearings easier.

Position finding and celestial navigation instruments

Index mirror: large polished plate that reflects light.

Telescope: optical instrument made of lens that magnifies objects.

Telescope clamp: reinforcing circle.

Eyepiece: lens the user looks through.

Telescope printing: lens adjustment.

Frame: structure that serves as the base for the different parts of the sextant.

Graduated arc: graduated edge of the arc.

Locking device: apparatus that holds the sextant in place.

Drum: graduated button used to take measurements.

Index arm: type of ruler that determines direction or measures an angle.

Screw to regulate small mirror: piece of metal used to adjust the horizon mirror.

Glass filter: colored transparent substance.

Horizon mirror: small polished glass plate that reflects light.

Glass filter: colored transparent substance.

This is an instrument which measures the angle between the celestial body and the horizon. A sextant can also be held horizontally to measure the angle between any two landmarks which allows for calculation of a position on a chart. Navigators’ sextants were primarily used for celestial navigation. The first sextant was made in 1757.

Taking a sight. A navigator would typically go out on the navigation bridge wing. He or she then takes an altitude and notes the exact time. Calculations are then made to determine the ship’s position. This is usually done when the ship is far from land, and lighthouses and other land based objects cannot be used to ascertain our position.

With the advent of the GPS, the marine sextant is slowly becoming obsolete. However, its use and the calculations is a mandatory part of all marine navigational examinations.