内容摘要：In her deposition, Ms Huang said that Zhihan was walking ahead of her on the Cliffs of Moher trail when she lost sight of him.

In her deposition, Ms Huang said that Zhihan was walking ahead of her on the Cliffs of Moher trail when she lost sight of him.

The court heard the case was then passed to detectives from the Online Child Abuse Investigation Team at Cheshire Police.Devices were seized from Clark's home where police found hundreds of messages to dozens of girls - many under the age of 16.

He had sent indecent videos to some girls and asked for them to send some back to him.Cheshire Police praised the complainants for their bravery and described Clark as a sexual predator who despite being in a position of trust, continued his crimes to "satisfy his own warped sexual desires".Sentencing him to eight years, Judge Simon Berkson said his crimes were "a parent's worst nightmare" and showed "clear grooming of young girls".

He said it was "well planned, sophisticated, criminal behaviour".As a result he said Clark had "lost everything" including his job, marriage and unsupervised access to his own young children.

He will face an extended four years on licence at the end of his sentence.

An NSPCC spokesperson said: "As a teacher Clark had a duty to keep children safe."We know that many household items were coloured with arsenic-based green pigments. It was even used in confectionery."

The trouble is, the combination of elements used is toxic and that's still a problem more than a century later. And it's a particular problem when it comes to old books.Victorian bookbinders used arsenic as well as mercury and chrome to create striking covers. And unlike domestic items, books have survived in archives around the world, creating a 21st Century problem from 19th Century fashion.

Prolonged exposure to multiple green books can cause low level arsenic poisoning.Long-term exposure can cause changes to the skin, harm to the liver and kidneys and a reduction in red and white blood cells, which can lead to anaemia and an increased risk of infections.