Steven Norris, chairman of Jarvis, has backed up his claim that the rail maintenance specialist will recover from a recent difficult period by nearly doubling his stake in the firm.Norris, a former Conservative transport minister, bought 300,000 shares at 7.5p a time. The shares have taken a downward turn since his last foray into the market, when he paid 10.8p a time for 200,000 shares.Jarvis's revenue in the year to March rose to £345.8m from £321.9m in 2008. Underlying profit fell to £5.1m from £7.5m, but after exceptional costs of£11.4m, losses were £6.3m. "The current economic conditions and Network Rail's decision to delay works created a difficult trading environment in the second half of the year under review and this is expected to continue through 2009-10," Norris said. "The prospects beyond that appear much more promising."Top Director BuysFairpoint Group (FRP) Director name: Mr Matthew PeacockAmount purchased: 100,000 @ 54.00p Value: £54,000Jarvis (JRVS) Director name: Mr Steven NorrisAmount purchased: 300,000 @ 7.50p Value: £22,500Top Director SellsGreystar Resources (GSL) Director name: Mr German del CorralAmount sold: 10,000 @ 163.24p Value: £16,324