Why did this happen? Please make sure your browser supports JavaScript and cookies and that you are not blocking them from loading. We are in active discussions with DEFRA to support and advance the creation of this new testing methodology. These particles have been linked to a number of health issues and can cause damage to the lungs - particularly in young and old people. Wood burners were lit for four hours at a time and, while operating, the levels of harmful particles was three times greater than when they were unlit.
This happened in the year of the 19th century.
( z0 event :mod ( z1 this ) :time ( z2 date-entity :century 19 ) )
(z0 / event
    :mod (z1 / this)
    :time (z2 / date-entity
              :century 19))
This happened in the year of the 19th century .
z0 :mod z1
z0 :time z2
z2 :century 0