In my young days, suffering with boils was not at all uncommon. Nowadays one rarely hears of this complaint. Why?

Boils are usually attributed to a staphylococcus infection of the skin promoted by rubbing or skin wear, leading to red lumps and pus-filled abscesses occurring most famously on the male neck under a stiff collar. Modern treatment is by antibiotics, including creams, but an older remedy is to take a tin hydroxide containing medicine, which by analogy can be colloquially termed “milk of stannesia”.

Boils virtually disappeared in the 1950s in the UK because of the large growth of canned food consumption, tin being found as a corrosion product in acidic foods packed in plain (ie. unlacquered) tinplate cans, giving a built-in body resistance. Their disappearance was slower in less-advanced countries - a study in Ireland at that time showed a five to ten-year lag.

With the greater use of lacquered cans, aluminium, polymer and Tetrapaks for fruit juices in particular it is possible that boils may return. But soft collars, the abandonment of ties and general “dressing-down” may also yield fresh sites for boils.

David Gabe, Loughborough

Boils are caused by ingrown hair, by foreign material lodged under the skin, but mainly by infected sweat glands. They are less common nowadays because of modern fabrics, which are more sensitive to the skin and reduce perspiration, and by the mass use of antibacterial soaps and cleansing agents, which reduce the risk of infection.

Alex Hill, Limekilns, Fife

When and where did the practice of the bent arm with fingers to the temple supersede the Roman straight arm salute?

In days of yore knights in armour would inspect their troops by trotting along the ranks on horseback. The troops would see the knights colours and to assist the men further in identifying the knight in battle, he would raise the visor on his helmet so that his face could be seen by all. Holding the visor open with one hand at forehead level evolved into the military salute we know today.

David Griffiths, Bromley, Kent

When does a copse become a wood, and a wood become a forest?

The boundaries of these three terms are all blurred by longstanding usage or, if you will, mis-usage. I suggest that a wood is always a wood, be it large or small and must consist of trees.

A forest is, though large, not entirely or necessarily composed of trees and may be presently or formerly reserved for hunting. The word seems to be increasingly popular over “wood” through transatlantic influence as does “ocean” over “sea”.

A copse is a stand of trees that are, or have been, managed and harvested, so, necessarily of limited range by its purpose; “coppice” is a rendering of idiosyncratic pronunciation though I have been told that “copse” and “copsing” are traditionally more correct.

A small stand of trees never intentionally managed would be more correctly a spinney, shaw or thicket, or if preserved for game shelter, a covert.

Bill Collett, Penryn, Cornwall

It is obvious why one side of a coin of the realm in the UK should be called heads, but why is the reverse side called tails?

A tail is simply the opposite to a head. (An animal's head is at the front end, its tail at the back end). Some countries see a coin similarly, as German Kopf oder Zahl, but the French say pile ou face, where pile (related to “pillar”) is the die with which the reverse side of a blank coin is stamped. Russians say orel ili reshka, eagle or curlicue, from the former representation of an eagle on the obverse and an ornate latter (the tsar's initial, as “A” for Alexander or “N” for Nicholas) on the reverse.

Adrian Room, Stamford, Lincolnshire

“Who's she - the cat's mother?” Why do uneducated people take exception to this pronoun?

Susan Kelly,London W5

By what process are the coats of badgers used to make shaving brushes and do they survive?

John Darrall, Cottesmore, Rutland

Where were army uniforms made, and by whom, before the invention of the sewing machine?

Mrs. S. Bell, Ashbourne Dorset

When did men, and boys, cease whistling, and why? Are the current tunes not suitable?

L.H.Rashbrook, High Wycombe

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