iay r s labour,ora day's journey exhausts their strength^ 

 Bat the heart toils whole weeks, whole months, nay 

 years, unwearied : is equally a stranger to intermis- 

 sion and fatigue. Impelled by this, part of the bTood 

 shoots upward to the head ; part rolls through the 

 whole body. 



But how shall a stream divided into myriads of chan- 

 nels, be brought back to its source ? Should any por- 

 tion of it be unable to return, putretaction,if not death, 

 must ensue. Therefore the ailwise creator has con- 

 nected the extremities of the arteries with the be^i;t- 

 ning of the vt-ius : so that the same force which darts 

 the blood through the former, helps to drive it through 

 the latter. Thus it is reconducted to the great cistern, 

 and there played oflf afresh. , 



Where two opposite currents wtfuld be in danger of 

 clashing, where the streams from the ?ena eava and 

 vena asctndens coincide, a fibrous excrescence inter- 

 poses, which like a pr 'jcc'ing pier, breaks the stroke 

 of each, and throws both into their proper receptacle. 

 Where the motio:i is to l><' speedy, the channels either 

 forbear to wind (as in the great artery which descends 

 to the feet) or to lessen in their dimensions, as in every 

 interval between all the ramifications. When the pro. 

 gress is to be retarded, the tubes are variously con. 

 volved, or their diameter contracted. Thus guarded, 

 the living flood never discontinues its course, but night 

 and day, whether we sleep or wak*, still perseveres 

 to run briskly through the arteries, and return softly 

 through the veins. 



B't farther, the great Creator has made us an in- 

 valuable present of the senses, to be the inlets of innu- 

 merable pleasures, ai d the means of the most valuable 

 advantages, 



The Eyp, in its elevated station, commands the most 

 enlarged prospects : consisting only of fluids, enclosed 

 \vithm coats, it shews us all the graces and glories of 

 nature. How wonderful, that an i.nage of the hiigc-st 

 mountuins ; and the widest landscapes, should enter 



