How will you separate a mixture containing saw dust, naphthalene and iron filings?

Explanation

When a magnet is brought near the mixture containing saw dust naphthalene and iron filings it attracts the iron filings. Thus iron filings are separated.
The mixture of naphthalene and saw dust are put in a china dish and covered with a perforated abestos sheet An inverted funnel is placed over the asbestos sheet.
The open end of the stem of the funnel is closed, using cotton wool. The china dish is heated The pure vapour of naphthalene solid pass through the holes in the asbestos sheet and condense on the inner side of the funnel The saw dust is left in the china dish.