 On 8 May they reached the Vaal River, and were prevented from crossing it until 17 May, by severe snow and rain on 13 May.Continuing northwards they met one of the Voortrekker leaders Andries Potgieter at present-day Potchefstroom in May 1841.Heading further north they made their way to the Magaliesberg entering the Magalies River catchment on 31 May.