LANCASHIRE tycoon Trevor Hemmings saw his main holding company return to profit last year.Chorley-based Northern Trust Group made a pre-tax profit of £2.6m compared to a loss of £7.1m last time. Revenues dipped 3.7% to £39.5m in the year to March, according to figures filed at Companies House.  The profit figure improved because the investments that were written off fell from £15m to £1.5m. However, the accounts still show exceptional items of £5.3m relating to investment activities.