Mcr'mo-Ryeland Breed of Sheep. 



439 



woolled breeds of ewes, in point of time. For if we begin witli loooewes, and sup- 

 pose the male and female produce to be annually equal, and I'le shearling ewes . be 

 continually crossed widi the Merino ram, it will be 8 years before we can obtain 

 125 shearling sheep of the fourth cross. 



This proposition, and the comparative inference from it, will best be demon- 

 strated by the following table, which supposes the experiment to c.^mmcnce m the 

 year 1 800, with looo RyelanJ ewes, and in which the number of crosses is marked 

 by the small figure on the right of each number. 



EWE PRODUCE. 



From this table it appears, that in 8 years there would be only 62- females, 

 and, consequendy, 125 of both sexes, of the fourth cross, and none of the fi^'h; 

 and tliai, in 10 years, there v/ould be from the coarser breed of ewes only 31^ 

 shearlmg ewes, and 6i-^ of bath sexes of the fifth cross, or requisite fineness; 

 whereas from the Ryelaiid ewes there would, at the same period, be of the same 

 fineness 937I: shearling ewes of the fourth cross, and of the fifth cross 315- ewes, or 

 in iouiid numbers, 969. To which add as many males, and the whole number will 

 be 1938; 



