<Sixth>. That the lessees shall be bound to leave upon the subjects hereby let a flock of Cheviot or black-faced ewes average quality, and not less in number than six hundred of equal proportion one, two, three, and four years of age, and shall be bound to hand the same over to the proprietors at the end of this lease, at the valuation of two persons to be mutually and specially chosen for the purpose. <Seventh>. That the lessees shall arrange that only one family shall be in the occupation of each holding at the expiry of this lease, and for at least one year prior thereto. <Twelfth>, It is hereby stipulated and agreed on by the lessors and lessees that this lease may be added to, altered, or modified, by simple letters exchanged between or modifications be found necessary in order to work out its different provisions and the lease being of a nature new and untried in Shetland, that it shall be interpreted as favourably as possible for the lessees, consistent with already expressed intentions of the two parties. RULES AND REGULATIONS to be entered into between the LESSEES under the foregoing Lease and their SUB-TENANTS referred to, and subscribed by the parties with special reference to said Lease. 1. No sub-lease shall extend beyond the term of Martinmas eighteen hundred and eighty. 2. Such local or other taxes as shall be levied upon tenants shall be duly paid by the sub-tenants according to the amount of their rents, or if advanced by the lessees shall be repaid to them by the sub-tenants. 3. Only one family shall be allowed to occupy each holding. 4. The sub-tenants shall be bound to maintain, keep, and leave at the end of their sub-leases in good tenantable condition, the houses and all permanent improvements handed over or that may be added during the existence of the sub lease. 5. The sub-tenants shall be bound to expend annually upon their respective holdings, in such manner as may be pointed out by the proprietor, or his factor improvements equal in value to the amount of the annual rent. During the first five years of the sub-lease, the lessees will allow annually an amount equal to one half of such permanent improvements as may have been executed in a satisfactory manner (said amount in no case to exceed one half of the amount of rent), and the sub-tenants shall be bound to pay at the rate of seven per cent. per annum on all advances so made during the period of endurance of their sub-leases. 6. Every sub-tenant shall be bound to follow a six-shift rotation of crops, according to the rules of good husbandry. During the first three years, as it may be impossible to follow the rotation, the sub-tenants are bound to follow such orders of cropping as may be pointed out by the proprietors or their factor and the lessees.