The Explorer at length arrived at Yuma.  Here the remainder of the party, including Dr. Newberry, having come across country, joined the expedition, and further preparations were made for the more difficult task above.  The craft was lightened as far as possible, but at the best she still drew two and one-half feet, while the timbers bolted to the bottom were a great detriment, catching on snags and ploughing into the mud of the shoals.  There were twenty-four men to be carried, besides all the baggage that must be taken, even though a pack-train was to leave, after the departure of the boat, to transport extra supplies to the end of the voyage, wherever that might be.  It is not easy to understand why so large a party was necessary.  Some few miles above Yuma they came to the first range of mountains that closes in on the water, suddenly entering a narrow pass several hundred feet deep.  Seven miles farther on, they went through a small canyon where another range is severed.  This was called Purple Hill Pass, while the first one was named Explorer’s Pass, after the steamer.  The first approach to a real canyon was encountered a short distance above.  Emerging from this, called Canebrake, from some canes growing along the sides, the Explorer ran aground, resting there for two hours.  They had now passed through the Chocolate Mountains, the same range that Alarcon mentions, and as he records no other he probably went no farther up than the basin Ives is now entering, the Great Colorado Valley.  Alarcon doubtless proceeded to the upper part of this valley, about to latitude thirty-four, where he raised the cross to mark the spot.  Two miles above the head of the canyon, the power of the Explorer was matched against a stiff current that came swirling around the base of a perpendicular rock one hundred feet high.  With the steam pressure then on, she was not equal to the encounter and made no advance, whereupon she was headed for a steep bank to allow the men to leap ashore with a line and tow her beyond the opposition.  Above, the current was milder, but the river spread out to such an extent that progress was exceedingly difficult, and Ives expresses a fear that this might prove the head of navigation, yet he must then have been aware (and certainly was when he published his report) that Johnson at that very moment was far beyond this with a steamer larger than the one he was on.  It was now January 17, 1858, and it was on January 23d, that Johnson was at the point where Beale intended to cross.  The steamer was used as a ferry and then left the same day for Yuma.  Captain Johnson with his steamboat had been to the head of navigation.  Ives and Johnson must now pass each other before the end of this month of December, and the meeting of the two steamers took place somewhere in this Colorado Valley, for, under date of January 31st, Ives says:  “Lieutenant Tipton took advantage of an opportunity afforded a few days ago, by our meeting Captain Johnson,