Unputdownable

With reference to your cover story, Dark Visions, ancient fear (July 17), I must say that the story was very enlightening. The writer had beautifully explained the causes associated with such a phenomenon. The article was both informative and interesting. Three cheers to The Telegraph for presenting us with the best articles and scientific facts every Monday. You are indeed an unputdownable newspaper.

T. R. Anand
Calcutta - 700 137

More anti-virus

With reference to Bits & Bytes (July 10), I would like to add a few more details about anti-virus products. Antivir does not support ad ware or spy ware or pop3 mail scanning in the free version and sometimes may also confuse users. Clam win is good but one has to download an exe file and the virus definition file following installation. Avast is another good anti-virus but is not updated frequently. But if anyone wants to spend money to install an anti-virus, then try Quick Heal.

Rudrodeep Biswas
Via email

Global warming

This refers to Cooling the earth (July 10). Global warming has become a serious threat to civilisation, mainly due to our inability to control pollution. The constant emission of industrial gases like carbon dioxide creates a thin film over the earth, which prevents heat absorbed by the earth to be dissipated. As a consequence, there is a gradual increase in the global temperature. The rapid rise of concrete structures along with the ruthless depletion of green belts have aggravated the situation. I personally feel that an attempt should be made to reduce the usage of fossil fuels by increasing the usage of renewable sources of energy like solar, wind and tidal energy as they are a logical solution in combating the existing environmental problems.

Somnath Majumdar
Baishnabghata

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