Concentration camp brothels remain a hushed-up chapter of the Nazi-era horrors. Now a German researcher has probed the dark subject -- and has revealed the meticulous cruelty of the so-called "special buildings."

Kicking them with his boots, the SS soldier drove Margarete W. and the other women prisoners out of the train and onto a truck. "Move the tarpaulin, put the flap down. Everyone get in," he yelled. Through the plastic window in the truck's canvas side, she watched as they drove into a men's camp and stopped in front of a barracks with a wooden fence.

 The women were taken into a furnished room. The barracks were different from the ones Margarete W., then 25, knew from her time at the Ravensbrück women's concentration camp. There were tables, chairs, benches, windows, and even curtains. The female overseer informed the new arrivals that they were "now in a prisoners' brothel." They would live well there, the woman said, with good food and drink, and if they did as they were told, nothing would happen to them. Then each woman was assigned a room. Margarete W. moved into No. 13.

The Treaty of Versailles between Germany and the victorious Entente powers was signed 90 years ago this weekend. Can the details of the settlement at the end of a war almost now beyond living memory still have any relevance for us?

Without the events of 11/9 (the fall of the Berlin Wall on 9 November 1989) and 9/11 (the attack on the World Trade Center in New York on 11 September 2001), it might have been easier to suggest that the results of the Paris Peace Conference and the subsequent gatherings that formally concluded the First World War had indeed faded into the background.

Even then, however, the widely held view that Versailles, and the other treaties signed in palaces in the Parisian suburbs in 1919 and 1920, held a key responsibility for the outbreak of a new major war in 1939 and hence for its consequences, might still have offered important reasons for reconsidering their negotiation and results.

Tipped with a sewing machine needle and finished with a tail made from a drinking straw, they looked more like a schoolboy's toy than a terrifying weapon. For Britain's wartime scientists, however, these tiny projectiles were the sharp end of a chilling project to secure victory over the Nazis by bombarding German troops with poisoned darts.

A secret file that details British research to develop the lethal anti-personnel darts, carrying a toxin likely to have been anthrax or ricin, casts rare light on the work that was carried out by the Allies during the Second World War into chemical and biological weapons that could be deployed against Hitler's forces.

The document, released at the National Archives in Kew, London, reveals how scientists at Porton Down in Wiltshire, the site of Britain's top secret weapons laboratory, worked between 1941 and 1944 to perfect the projectiles to ensure the maximum number of casualties and the quickest death for enemy soldiers.

There is new evidence in the debate regarding the 1908 Tunguska event that destroyed 80 million trees in Siberia.

Researchers say that clouds that form at the poles after shuttle launches are due to the turbulent transport of water from shuttle exhaust.

Similar clouds were visible at night long after the Tunguska event.

The Geophysical Research Letters study suggests that an icy comet, rather than a meteor, must have been responsible for the event.