S1:          Forecasting the weather has always been a difficult business. P :           During a period of drought, streams and rivers dried up, the cattle died from thirst and were ruined. Q :          Many different things affect the weather and we have to study them carefully to make accurate forecast. R :          Ancient Egyptians had no need of weather in the Nile Valley hardly ever changes. S :           In early times, when there were no instruments, such as thermometer or the barometer, man looked for tell-tale signs in the sky. S6:          He made his forecasts by watching flights of the birds or the way smoke rose from fire. The Proper sequence should be: