Soon after his graduation, Slaughter was ordered to California and took passage by a sailing vessel going around Cape Horn.

The vessel was seven months making the voyage, and Slaughter was sick every moment of the time, never more so than while lying at anchor after reaching his place of destination.

On landing in California he found orders which had come by the Isthmus, notifying him of a mistake in his assignment; he should have been ordered to the northern lakes.

He started back by the Isthmus route and was sick all the way.

But when he arrived at the East he was again ordered to California, this time definitely, and at this date was making his third trip.