Top dog for brain power
QUESTION Dogs are said to be able to respond to 89 words. What are they?
PSYCHOLOGY and neuroscience researchers Catherine Reeve and Sophie Jacques of Dalhousie University in Halifax, Canada, reported that dogs can understand an average of 89 words and phrases, but there is a lot of variation between breeds.
The most intelligent dog in their study, a border collie, was able to recognise 215 words or expressions, while a terrier could respond to only 15.
Ten words were recognised by at least 90 per cent of dogs. In descending order, they are the dog’s name, sit, come, good girl/good boy, down, stay, wait, no, OK and leave it.
Various words were responded to by 10 per cent or fewer dogs: wipe your feet, whisper, loud, the dog walker’s name, kennel’s name and another pet’s name.
Certain breeds were found to be more adept at responding to verbal cues. Purebred herding dogs and toy dogs had the largest vocabularies, while sports/gun dogs and terriers were the least wordy.
Professional canines, such as military or police dogs, tended to recognise twice as many words as other dogs.
Florence Dowell, Shaftesbury, Dorset.
QUESTION Was there a by-law in 19th century Northwich, Cheshire, whereby houses had to be built so they could be moved to enable mining?
NORTHWICH’S fortunes were built on salt. Rock salt was laid down in the region 220million years ago during the Triassic period and has been extracted since Roman times.
A by-law was passed in 1881 to ensure a lightweight, timber-framed style of construction was used for all new buildings so they could withstand, or even be moved, if there was subsidence.
In 1891, the Brine Pumping (Compensation For Subsidence) Act was passed to respond to claims of damages.
Back in the time of Charles I, more than 200 wyches or salt manufactories were at work in Northwich.
As more mining took place, the ground underneath the town became a veritable warren of tunnels, often flooded with water. Subsidence was always a problem, but in the 1870s, the practice of pumping out the brine from flooded mines to supply the local salt factories caused extensive subsidence and many of the buildings collapsed.
The light timber framing of the Middle Ages was re-introduced, which gives the town its unique character today.
The buildings were wooden framed with infill panels of brickwork that rested on a timber (later steel) ring beam at ground level. This means the building could be jacked up and the foundations raised in case of subsidence.
Lime mortar used between the brick panels gave the building some flexibility in case of minor ground movement.
Several houses had to be moved. Famously, the Bridge Inn, which weighed 55 tons, was moved 185 ft in 1913.
The town’s bridges, built in the 1890s, were designed as partially floating structures to counteract ground movement. The 429-ton Hayhurst Bridge, supported by four floating pontoons, was the world’s first electrically operated road swing bridge.
Alun Davies, Sandiway, Cheshire.
QUESTION Why do physicists sometimes refer to a theory as a ‘spherical cow’?
TO PHYSICISTS, the spherical cow is an idealisation, a humorous metaphor for highly simplified scientific models of complex phenomena.
The term has been known since the early 1950s and is thought to have started as a joke.
A dairy farmer wants to increase his production of milk, so he hires three consultants: an engineer, a psychologist and a physicist.
After a month, the engineer reports: ‘If you want to increase milk production, you need more efficient pumps.’
The psychologist reports: ‘Happy cows produce more milk. Paint the milking stalls green to make the cows think they are frolicking in the fields.’
The physicist responds: ‘Consider a spherical cow of radius R and mass M, which ingests a steady stream of grass at a constant rate G . . .’
The joke is funny to physicists because most of the tools we learned as students to solve problems involved the construction of idealised models that drastically simplified real phenomena to the point where they can be described by simple mathematical equations.
The simple approach can be just as effective. Imagine that you dropped a twig into a river and would like to know its velocity. There are many things you might need to consider to solve this.
How rigid is the twig? Did it rotate or oscillate? What was the air and water resistance? What is the velocity of the water and is it constant? What about gravitational effects?
You would eventually ignore all of these factors and deduce a value based on a simplification — the distance that the twig travelled in a given amount of time.
S. F. Barnes, Birmingham.
QUESTION What did cowboys wear?
FURTHER to the answer about cowboys favouring Derby (pronounced Durby in the U.S.) hats, this headgear took on an unusual role in the jazz age.
It was much favoured by trumpet and trombone players, who would blow into a hat to give a haunting, mellow sound. They also fanned the end of the trumpet for an exciting wah-wah effect.
In a film of The Duke Ellington Orchestra, the whole trumpet section does this, and it sounds fantastic.
By the late 1920s, the musicians used ‘Derby hats’ made of aluminium, and much later fibreglass. I have one, but haven’t used it for many years.
Clive Madgin, Savoy Jazz, Durham.
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