744 KANSAS CITY REVIEW OF SCIENCE. 
the last two or three miles run along the shore of the Panama Bay, and the ship 
channel will be made by simply dredging out the Bay. 
Although a Frenchman is at the head of this great work, and most of the 
capital is furnished by Europeans, yet American ingenuity is largely drawn upon 
for the active propelling force. Without the American dredging machines it 
would take so long to dig the canal that it would almost be impossible to raise 
the necessary capital, the possibility of earning dividends being too remote. 
With the American dredging tnachines the excavating is done with such rapidity 
as to bring the completion of the work within a reasonable period. 
There are American dredging machines and steam excavators and Ameri- 
can contractors all along the line. In some places a single one of these machines 
is throwing out earth at the rate of 5,000 cubic yards a day. Temporary rail- 
roads must be built at every cut, and, in fact, wherever it is necessary to carry 
the excavated material to a dumping ground. At the Emperador section, which 
is only three miles long, twelve locomotives are at work hauling away the earth 
thrown out by the excavators. In the Gorgona section an immense dam and reser- 
voir a,re being constructed, which will receive the waters of the Upper Chagres. 
About 15,000 men, mostly from Carthagena and Jamaica, are employed on 
the canal. The mortality among them has not been as great as was expected. 
The Europeans have suffered some from the climate. The rainfall at Aspin- 
wall last year was 118.02 inches, and at Panama 36.62 inches. Twenty-five 
and a half inches of rain fell at Aspinwall in the month of August. Although 
he has no accurate information on the subject, Lieut. Rogers believes that 
$40,000,000 have been already expended on the canal. This is one-third of the 
estimated cost. Whether the remaining $80,000,000 will be sufficient to com- 
plete the work is problematic. — National Republican. 
RIVER IMPROVEMENTS. 
WM. H. MILLER. 
The improvement of the Mississippi River is a subject in which the people 
residing in the valley of that stream have felt more or less interest from the 
time of the earliest settlement. The first effort in that direction was made at 
New Orleans within a short time of the first settlement there, and consisted of 
the construction of a short levee to prevent the inundation of the village by the 
annual floods. This form of improvement continued with a gradually increasing 
interest until the outbreak of the late civil war. After the Louisiana Territory 
became American possessions, and the settlement of the valley made the protec- 
tion of the low lands more of an object and provided the wealth and population 
to prosecute such improvements, they were carried forward with greatly increased 
energy, and by State and local aid were pushed forward with such magnitude that 
by the year 1858 twenty-two hundred miles of levee had been constructed, ex- 
