Good Questions: Why canoes are male and ferries female

TUNNELS, short sleeps, overseas communications and gender have been among the things worrying readers in the past week. Here are the results of our investigations.

How was Hezekiah's tunnel constructed? This is a tunnel carved through solid rock on the instructions of King Hezekiah in 700BC to bring water from a spring just outside the walls of Jerusalem to a reservoir inside the city. It is mentioned in II Kings xx, 20. This subterranean tunnel, 1,700ft long, was apparently dug by two teams of men starting at opposite ends; a plaque marks where they met. How could two teams of tunnel diggers setting out on opposite sides of a hill calculate how to set a course that would ensure they met in the middle? The tunnel is not in a straight line, but bends a number of times and has a uniform gradient along its length. (David Houston, Glasgow)

We don't see the problem. The simple answer is that they probably called in the Egyptians. Even though the date of this tunnel was more than a century before Pythagoras, his theorem may already have been known to the ancient Egyptians. They certainly knew specific examples of the lengths of sides of right-angled triangles, and even without trigomometry had the skills needed to make scale drawings of the results of surveying. A series of beacons on the hill, each visible from the previous one, would be all it needed to plan a route for the tunnel, while plumb-lines and right-angles (or spirit levels) would be sufficient to handle the gradient.

If variations in the resistance of the rock necessitated unplanned changes of direction, it could be necessary to modify the gradient, but a steady flow of water could be ensured by finalising the floor of the tunnel after the two ends have met. As long as measurements of angle and gradient are kept accurately, they should meet as planned.

All major ancient civilisations developed accurate methods of tunnelling. The Babylonians built a brick-lined subway 3,000ft long beneath the Euphrates before 2000 BC; the Egyptians had copper saws and reed drills for rock-cutting at the time of Ramses II around 1250BC; and Pythagoras himself may have advised on the building of the 3,400ft water tunnel on Samos.

Principal source: Encyclopaedia Britannica.

What is the origin of 'having 40 winks'? Why 40? How long is a wink? (John Howard, Market Rasen, Lincs)

A wink is as long as it takes to close your eyes, and the word seems to have been used for brief eye-closing or sleep since the middle ages. The OED cites one reference from 1362: 'thenne wakede I of my wink'. Equally, the number 40 has been shorthand for an indefinite largeish number since around the same date. With the rains of the Flood falling for 40 days, Noah opening the windows after another 40 days, Moses 'in the mount 40 days and 40 nights', Elijah fed by ravens for 40 days, St Swithin's Day predicting good or bad weather for the next 40 days and Mosaic law forbidding the infliction of more than 40 lashes on an offender, the number is everywhere. Even the word 'quarantine' reflects the same obsession with the number 40.

Bearing all this in mind, the curious thing is that the phrase '40 winks' seems to have made its first appearance in 1828. Perhaps before then such a secular use would have been frowned upon, when the antecedents were so firmly rooted in religious beliefs.

Sources: Brewer's Dictionary of Phrase and Fable; Everyman's Modern Phrase and Fable; Oxford English Dictionary.

When I send a letter abroad, how is the money I have spent on the purchase of a stamp shared among the carrier of the letter, the UK postal service and the postal service of the country of receipt? Similarly, if I make an overseas telephone call, who receives payment, and who agrees the rates? (B Lake)

There are three systems for mail, two organised by the Universal Postal Union (an agency, now part of the United Nations, concerned with international postal matters), the other devised by the European Posts and Telecommunications organisation CEPT. The first two systems are a flat rate for small quantities, or a rate determined by weight for bulk. The European system is related to numbers and volume. Each consignment of international mail enters a country with a document listing number and weight. At the end of each accounting period, equalising payments are made between each pair of countries.

Although the system appears to work well, having led to no serious disputes, there is some unfairness towards countries receiving a large amount of lightweight mail. Discussions are in progress concerning a possible system more directly related to handling and delivery costs.

UN sanctions against Serbia and Montenegro, incidentally, apply to parcels but not to personal letters.

With telephone calls, there is no universal agreement and no organisation controlling reconciliation charges between nations. The carrier who takes the call receives the payment, but rates are agreed between the carriers at both ends. Between Britain and the United States, for example, there are many different carriers, with each of whom both BT and Mercury have to agree rates.

The level of competition on different routes explains why phone rates to one country may seem better value than those to another.

Sources: Post Office; British Telecom.

Can anyone explain why Latin-based languages (and possibly others) assign masculine or feminine gender to words (eg 'table') that are neuter? What purpose is served by this? It seems merely to complicate the language by requiring adjectives to agree with the nouns. (Philip Barron)

The underlying question here is one of the motivation behind assigning of nouns to the various 'noun-class' systems of the language. In some languages these systems may be apparently gender-linked; in others they may provide information about physical or functional properties, or be related to social status.

In 1890, the prevalent theory was that advocated by Grimm: that gender-classification in Indo-European languages was based on a projection of human sex-related characteristics on to inanimate objects. Brugmann, however, proposed in 1899 that gender categories originated from the original shape and sound of the word, which is the most generally held view today. As the International Encyclopaedia of Linguistics put it: 'The Brugmannian position has gained general acceptance in modern linguistics; noun-class systems, and gender in particular, are often cited as paradigmatic instances of arbitrariness in language structure.' Any original logic behind the system will have disappeared (or been 'diachronically eroded') as the language evolved.

Recent research, however, has leaned back towards Grimm, with studies of Bantu and the Dyirbal language of Australia suggesting an original link between gender and either meaning or mythic association. In the Kxoe language of the west Caprivi strip in South West Africa and Namibia, masculine gender implies long, narrow or strong, while feminine suggests short, round, broad or weak. So canoes are male and ferries are female.

This does not help explain why, in German, spoon, fork and knife are respectively masculine, feminine and neuter.

Sources: International Encyclopaedia of Linguistics; Encyclopaedia Britannica, Cambridge Encyclopaedia of Language.

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