60 ANNUAL REPORT 
Mr. Newhouse is experimenting with other mixtures which he 
thinks will be even better than the one given above. One of the railway 
officials said that he believed this would be cheaper than paint because of 
the greater length of life. 7 
LININGS IN WARSHIPS.* — 
Cement mortar is used in certain places both upon the inner and 
outer steel skins of warships, particularly where it would be difficult or im- 
practicable to prevent corrosion by paint alone. Cement mortar is also 
used in corners to prevent water standing in them; when a small space is 
inaccessible for cleaning or painting, it is filled solidly with cement 
mortar. 
The use of cement is restricted to the minimum possible, and if 
satisfactory paint could be found for all locations, this mortar would 
not be used at all for protection of metal. The usual proportions are, 1 
cement, 2 sand. For all metal protection it is applied as thin as possible, 
never over 3 inches thick. 
CEMENT HARDENED QUICK SAND. 
Mr. Robert L. Harris, M. Am. Soc. C. E., patented in 1891, a device 
for hardening quicksand by means of cement grout injected into the sand. 
Those who have ever attempted to carry on excavation or construc- 
tion of any kind in quicksand know how discouragingly expensive such 
work is. Mr. Harris’ method is to drive pipes into the quicksand to the 
required depth and from four to eight feet apart, and then by attaching 
pumps to alternate pipes and pumping in water under pressure circula- 
tion is begun between these pipes and the ones left open. After circulation 
has been established and sufficient sand removed, cement grout is pumped 
in to take the place of the displaced sand. As soon as the grout appears in 
the open pipes they are capped and the pumps are run until a strong 
pressure is obtained to force the grout into the surrounding sand and 
then left to stand until the cement has time to set. The pipes are then 
raised a foot or more and the operation repeated. Some tests were made 
at Providence, R. I., which seemed to indicate that it would prove quite 
successful under favorable conditions. It was especially recommended 
for work in coarse sand or gravel, also as an aid to prevent large flows 
of water into trenches. : 
In erecting a bridge over the Danube at Ehingen, Bavaria, in 1898, 
the method of pumping grout into water bearing gravel was used very 
successfully. One and one-half inch pipes spaced about 18 inches to 20 
inches apart were driven to bed rock and grout forced in under pressure, 
the pipes then drawn up and the operation repeated. Where the gravel 
did not contain large quantities of sand the grout was found to have pene- 
*Information received from Mr. W. L. Capps, Chief Constructor, U.S. N. 
