It is not definitively known what Stonehenge was used for. Some believe it was used for sacrifices, and others say that it was for non-sacrificial rituals involving star counting and/or the predicting of various astronomical phenomena such as eclipses. More recent ideas are moving away from the idea that Stonehenge had complex 'astronomical' functions. However it was certainly set up in respect of the Midwinter Solstice.
It was not used as a barometer.
used for a clock
Pagans.
At Stonehenge human remains were found as well as tools used to help constructing the henge.
limestone
Stonehenge has not been used for thousands of years so no one knows the answer to this.
Stonehenge has no official ceremonial use today, other than a tourist attraction.
sightseeing and tourism.
clay
stonehenge
Stonehenge was used to track the stars and, therefore, could be also identify the time of year it was.
Stonehenge is in the country, but there is a guided audio tour and a giftshop on the Stonehenge site.