342 STATE BOARD OF AGRICULTURE. 



department to you, for your support and encouragement in our Experi- 

 ment Station activities during the past year. 



Respectfully submitted, 



M. M. McCOOL, 



Soil Physicist. 

 East Lansing, Mich., June 30, 1917. 



REPORT OF THE DIVISION OF FARM MECHANICS. 



Director R. S. Shaw, College: 



Dear Sir — Following is a brief report on the work carried on by the 

 Division of Farm Mechanics for the year ending June 30, 1917 : 



For the past two years interest has been manifested in the application 

 of marl to soils as a substitute for lime. Much of the marl is located in 

 beds underlying small marshes and lakes and is, therefore, inaccessible 

 by ordinary means of excavation. These beds are also too small or in- 

 accessible to transportation facilities to make a large commercial plant 

 profitable. A demand has grown for some means of obtaining the sub- 

 merged marl for use in the vicinity of the bed. 



A small plant which could be owned by a group of 4 or 5 farmers or a 

 small contractor, and which could be made portable, has seemed desir- 

 able. A thorough investigation of manufactured equipment of this na- 

 ture showed nothing which would meet the requirements either as to in- 

 vestment or practicability. Some investigation was made of methods at- 

 tempted to handle marl under the conditions named. From these ob- 

 servations and a study of the marl beds it appeared that the diaphragm 

 pump could be used. Pumping tests with this type of pump showed that 

 marl more than 50% solid could be pumped efficiently. Field tests in- 

 dicated, however, that the marl did not flow freely enough to keep the 

 suction hose filled and consequently too great a volume of water was 

 pumped. To exclude the water a bell-shaped end was used on the suc- 

 tion hose, having an internal hand-operated agitator for cutting the marl. 

 Tests of various kinds of agitators showed them to be inadequate and 

 consequently it became difficult to sink the bell as fast as the marl could 

 be pumped. As the simplest means of securing mechanical agitation a 

 machine having a movable arm, similar to a bucket dredge arm, — this 

 arm carrying the suction hose, and a scoop at the end of the arm was 

 devised. This scoop is designed to deliver the marl to the suction hose, 

 from whence it could be pumped and delivered through hose or pipe to 

 any reasonable distance to the shore or solid ground. This machine has 

 not been completed so results cannot be given. 



Practically the only question to be Avorked out in this problem is that 

 of agitating and starting the marl. It has been demonstrated that it 

 can be pumped efficiently, that it can be conveyed through troughs or 

 piping, and that it can be drained and dried by allowing to stand for 

 some time; also that it can be handled satisfactorily when dried with a 

 wagon or manure spreader. 



It is recommended that experiments be continued further at least un- 

 til the feasibility of pumping be determined. 



