“ But to prevent this privilege from being carried to extreme lengths, the provision for an average was qualified by saying 'the maximum number at any one time not to exceed 11,500 head.' The purpose of that provision, as thus qualified, was to define the grazing which might be done for the minimum rental of $31,950-in other words, to show that the grazing which might be done without further payment was limited to an average of 9,000 cattle. ”

“ We think it is neither a penalty nor liquidated damages. It was not to be paid for any breach of contract, but as compensation for particular grazing contemplated in the lease and not covered by the rental otherwise fixed. Whether the state statute could affect a contract made by the United States on behalf of Indian wards need not be considered.
At the trial it appeared that the additional cattle were admitted to and grazed on the leased area by one of the lessees, who had special charge of the operations under the lease ”

“ As the three contentions before stated all depend on a contrary construction they must fail.
The $4.50 rate is assailed as being a penalty or liquidated damages, and therefore condemned by a statute of the state. ”