WATER SUPPLY. 63 
were so associated with features of the topography that some estimate of 
their quantitative values could be made. The data which became thus 
available were collated for Professor Henry by Mr. Miller, a gentleman 
who himself took part in the navigation, and of whom I have already had 
occasion to speak. His results agree very closely with those derived from 
an independent investigation of my own, to which I will now proceed. — 
Antelope Island is connected with the delta of the Jordan River by a 
broad, flat sand bar that has been usually submerged but occasionally 
exposed. It slopes very gently toward the island, and just where it joins 
it is interrupted by a narrow channel a few inches in depth. For a num- 
ber of years this bar afforded the means of access to the island, and many 
persons traversed it. By combining the evidence of such persons it has 
been practicable to learn the condition of the ford up to the time of its final 
abandonment. From 1847 to 1850 the bar was dry during the low stage 
of each winter, and in summer covered by not more than 20 inches 
of water. Then began a rise which continued until 1855 or 1856. At 
that time a horseman could with difficulty ford in the winter, but all com- 
munication was by boat in summer. Then the water fell for a series of 
years until in 1860 and 1861 the bar was again dry in winter. The 
spring of 1862 was marked by an unusual fall of rain and snow, whereby 
the streams were greatly flooded and the lake surface was raised several 
feet. In subsequent years the rise continued, until in 1865 the ford became 
impassable. According to Mr. Miller the present height was attained in 
about 1868, and there have since occurred only minor fluctuations. 
For the purpose of connecting the traditional history as derived from 
the ford with the systematic record that has now been inaugurated, I visited 
the bar in company with Mr. Miller on the 19th of October, 1877, and made 
careful soundings. The features of the ford had been minutely described, 
and there was no uncertainty as to the identification of the locality. We 
found 9 feet of water on the sand flat, and 9 feet 6 inches in the little channel 
at its edge. The examination was completed at 11 a. m.; at 5 p. m. the 
water stood at 0 feet 10 inches on the Black Rock pillar; and on the follow- 
ing day at 8 a. m. we marked its level at the place where the Farmington 
pillar now stands, our mark being 2 feet 2 inches above the zero of the pillar. 
