The log

Given that you know the direction in which you have been travelling, the next vital ingredient of'dead reckoning' classical navigation is how far you have come. This is ascertained by using a log.

In ancient times, mariners literally guessed their distance run. Having made a number of ocean crossings myself without using a log, I can testify to the surprising accuracy of a well-tuned observer's eye aboard a ship with which lie is familiar.

However, since any instrument should be an improvement over no instrument, it wasn't long before mariners came up with a system of measurement.

The original type of log - still in use well into the nineteenth century - worked on 'speed per hour', which, multiplied by the number of hours until the next reading, gave the distance run. Except in a racing yacht, distance run is what the navigator usually wants. Speed is only of interest if you are shaping a course and need to predict how far you may travel in the next hour. Your speed now in a sailing boat gives no more help with your ETA than how far you ran in the last hour. Speed is merely useful as a means of determining distance. The present fixation with Sve did 8.7 knots today' sounds rather like a schoolboy boasting that his father's car is capable of 103 mph, according to the maker's propaganda. Both pieces of information are largely irrelevant in real life.

The original log worked as follows: a fan-shaped 'log chip' attached to a knotted line wound on to a reel was hove over the stern of the ship. The chip, or log, held its position in the water and dragged out the line as the ship sailed away from it. The knots in the line were made at intervals representing 1 nautical mile per hour. If 8 knots ran out in a given time, measured by a sand-glass, the vessel was logging 8 nautical miles per hour. Hence the term 'knot' and hence the name 'log' which is still attached to the most sophisticated electronic distance measuring device.

How To Have A Perfect Boating Experience

How To Have A Perfect Boating Experience

Lets start by identifying what exactly certain boats are. Sometimes the terminology can get lost on beginners, so well look at some of the most common boats and what theyre called. These boats are exactly what the name implies. They are meant to be used for fishing. Most fishing boats are powered by outboard motors, and many also have a trolling motor mounted on the bow. Bass boats can be made of aluminium or fibreglass.

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