

THE FARMER AT HOME. 359 



vdnds, the sand on the seashore is driven inland, covering the ground 

 o a certain distance, and leaving an elevated ridge at the further 

 >oundary ; succeeding winds blow this forward, and at the same time 

 ring fresh sand to supply its place. 



In the sixth volume of the Transactions of the Irish Academy, an 

 tccount is given of the encroachment of the sand over some parts of 

 reland. Trees, houses, and even villages, have been covered or sur- 

 ounded during the last century. The roofs, still rising above the 

 vvaste, attest the period and the progress of desolation. The loose 

 sands of Egypt are thus spreading over the plains that border the 

 Nile, and burying the monuments of art, and. the remembrance of 

 former cultivation. Palmyra, in Asia Minor, that once supplied an 

 abundant population with food, now scarcely affords a few plants to 

 the camel of the wandering Arab. By planting and irrigation, man 

 can fix limits to the moving wastes of sand ; but despotic power, more 

 destructive than the winds of the desert, unnerves the arm of industry, 

 and dashing the cup of enjoyment to the ground, consigns flourishing 

 and fertile districts to eternal sterility and solitude. 



SAP. The water in which the roots of a plant are immersed is 

 gradually absorbed, and during the season of vegetation, it ascends 

 through the vessels of the stem with great rapidity, and with great 

 force, but still limpid, tasteless and inert, possessing only the proper- 

 ties of the pure water from which it was derived. This fluid consti- 

 tutes the sap. In some plants, and at certain seasons, it is particu- 

 larly abundant. If wounded in the spring, previous to the expansion 

 of their buds, the sap of the vine, maple or birch, flows profusely, but 

 at midsummer, after the leaves are fully developed, the " tears of the 

 vine " are comparatively few. It is riot unusual, in this country, to 

 collect one or two hundred pounds of sap from a single maple of ordi- 

 nary size, and we are told that a birch tree, when wounded, has been 

 known to discharge a quantity equal to its own weight. Yet, at mid- 

 summer, when the noble energies of the vegetable are exerted, these 

 trees rarely bleed at all. The flowing of the sap is usually regarded 

 as the effect of its accumulation in the vessels, at a season when there 

 are no leaves through which, in the form of vapor, it may escape. 

 Dr. Smith, however, regards it as the effect of heat, operating on the 

 irritability of the plant, and he considers it as the first step towards 

 the revival of vegetation from the torpor of winter. To this hypo- 

 thesis there are very serious objections, for many trees bleed in the 

 autumn after the leaves begin to fade and fall, as well as in the spring 

 before the buds are open 



SAUSAGE-MEAT CUTTER. This machine, by the labor of 

 one man, is capable of cutting readily from eighty to one hundred 

 pounds of meat per hour, the person feeding the machine ; thus leaving 

 the mass cut sufficiently fine and uniform. The process is simply 

 putting in the meat at the small end of the cone, through the hopper, 



