Upper panel: ¹³CO(1–0) emission integrated from −4.5 to 15.0 kms^-1 from the GRS (Jackson et al. 2006). The cloud G052.24+00.74 is on the left side. This cloud is connected with the neighbouring cloud G051.69+00.74 by some filamentary gas wisps. Channel maps of the region can be found in Appendix A. Lower left panel: composite three-color image of the ¹³CO(1–0) emission from the Spiral Cloud G052.24+00.74. Red: 6.52 <v_lsr< 15.0kms^-1; green: 3.12 <v_lsr< 6.10kms^-1; blue: −4.53 <v_lsr< 2.7kms^-1. The velocity centroid map and velocity FWHM map can be found in Appendix D. Lower right panel: Spitzer GLIMPSE (Benjamin et al. 2003) and MPISGAL three-color image of the Spiral Cloud G052.24+00.74. Red: 24 μm; green: 8 μm; blue: 3.6 μm. Overlaid contours are the velocity-integrated ¹³CO(1–0) emission (integrated from −4.5 km s^-1<v_lsr< 11.5km s^-1). Contours correspond to 5.1, 10.2, 15.3 Kkms^-1. The white diamond at the centre stands for a star cluster discovered in the GLIMPSE survey (Mercer et al. 2005), and the green stars stand for H ii regions collected from the literature (Lockman 1989; Urquhart et al. 2009).