Now came a rolling region, covered with blue grass and dotted with groves of cedars, the earth generally hard and smooth and the marching easy. Striking southward, they reached a point where the plateau culminated in a low ridge, and saw before them a long gentle slope of ten miles, then a system of rounded hills, and then mountains. "Halt here," said Thurstane. "We must study our topography and fix on our line of march." "You'll hev to figger it," replied Glover. "I don't know nothin' in this part o' the world." "Ye ain't called on to know," put in Sweeny. "The liftinant'll tell ye." "I think," hesitated Thurstane, "that we are about fifty miles north of Cactus Pass, where we want to strike the trail." "And I'm putty nigh played out," groaned Glover. "Och! _you_ howld up yer crazy head," exhorted Sweeny. "It'll do ye iver so much good." "It's easy talkin'," sighed the jaded and rheumatic skipper. "It's as aisy talkin' right as talkin' wrong," retorted Sweeny. "Ye've no call to grunt the curritch out av yer betthers. Wait till the liftinant says die." Thurstane was studying the landscape. Which of those ranges was the Cerbat, which the Aztec, and which the Pinaleva? He knew that, after leaving Cactus Pass, the overland trail turns southward and runs toward the mouth of the Gila, crossing the Colorado hundreds of miles away. To the west of the pass, therefore, he must not strike, under peril of starving amid untracked plains and ranges. On the whole, it seemed probable that the snow-capped line of summits directly ahead of him was the Cerbat range, and that he must follow it southward along the base of its eastern slope. "We will move on," he said. "Mr. Glover, we must reach those broken hills before night in order to find water. Can you do it?" "Reckon I kin jest about do it, 's the feller said when he walked to his own hangin'," returned the suffering skipper. The failing man marched so slowly and needed so many halts that they were five hours in reaching the hills. It was now nightfall; they found a bright little spring in a grassy ravine; and after a meagre supper, they tried to stifle their hunger with sleep. Thurstane and Sweeny took turns in watching, for smoke of fires had been seen on the mountains, and, poor as they were, they could not afford to be robbed. In the morning Glover seemed refreshed, and started out with some vigor. "Och! ye'll go round the worrld," said Sweeny, encouragingly. "Bones can march furder than fat anny day. Yer as tough as me rations. Dried grizzly is nothin' to ye." After threading hills for hours they came out upon a wide, rolling basin prettily diversified by low spurs of the encircling mountains and bluish green with the long grasses known as _pin_ and _grama_. A few deer and antelopes, bounding across the rockier places, were an aggravation to starving men who could not follow them. "Why don't we catch some o' thim flyin' crachurs?" demanded Sweeny.