Fog had begun to develop and from about 03:50 became very thick. It remained for about four hours, then began to lift. Just before dawn at 05:00, it was so dense that objects could not be seen away, but by this time most of the infantry had crossed the wadi. However, the fog made it impossible for Dallas to reconnoitre the proposed battleground, and he waited at El Breij for it to lift while his two leading brigades moved slowly forward. Visibility was improving about 07:30, and by 07:55 the fog had lifted sufficiently for heliographs to be used. However, all aircraft in No. 1 Squadron had to return to their new landing ground at Rafa, as nothing of the ground could be seen from the air. Dallas' 53rd (Welsh) Division was moving forward, despite the fog to make a direct assault on Gaza. At 05:20, the division's 158th (North Wales) and the 160th (Welsh Border) infantry brigades were crossing the Wadi Ghuzze while the 159th (Cheshire) Brigade was in reserve. By 06:50 the 160th (Welsh Border) Brigade had moved towards Shaluf and the 158th (North Wales) Brigade was moving towards Mansura, but they were ordered to slow down because artillery support may not be available, if the fog were to suddenly lift. By 07:50, the leading battalions were approaching Sheikh Seehan without having encountered any Ottoman defenders. Between 08:15 and 08:55 hostile planes flew over the advancing infantry, firing their machine guns into the columns. At 08:30 the 160th (Welsh) Brigade was about from Gaza, with their leading battalion southwest of the commanding heights of their main objective, Ali Muntar. The 158th (North Wales) Brigade had reached Mansura, and by 09:30 they were three quarters of a mile (1.2 km) north of the 53rd (Welsh) Division's headquarters at Mansura.