340 Professor Playfair’s Description 
be brought down. In a country where there is little entei’prlse, 
few capitalists, and where he was himself a stranger, this was 
not the least difficult part of Mr Rupp’s undertaking. 
The distance which the trees had to be conveyed is about 
three of the leagues of that country, or, more exactly, 46,000 
feet. The medium height of the forest is about 2500 feet ; 
(which measure I took from General Pfyffer’s model of the 
Alps, and not from any actual measurement of my own). The 
horizontal distance just mentioned, when reduced to English 
measure, making allowance for the Swiss foot, is 44,252 feet, 
eight English miles and about three furlongs. The declivity is 
therefore one foot in 17.68; the medium angle of elevation 3^ 
14" 20'. 
This declivity, though so moderate on the whole, is, in 
many places, very rapid ; at the beginning the inclination it is 
about one-fourth of a right angle, or about 22° 30' ; in many 
places it is 20°, but nowhere greater than the angle first men- 
tioned, 22° 30'. The inclination continues of this quantity for 
about 500 feet, after which the way is less steep, and often con- 
siderably circuitous, according to the directions which the rug- 
gedness of the ground forces it to take. 
Along this line the trees descend, in a sort of trough, built 
in a cradle form, and extending from the forest to the edge of 
the lake. Three trees, squared, and laid side by side, form the 
bottom of the trough ; the tree in the middle having its surface 
hollowed, so that a rill of water received from distance to dis- 
tance, over the side of the trough, may be conveyed along the 
bottom and preserve it moist. Adjoining to the central part, 
(of the trough,) other trees, also squared, are laid parallel to the 
former, in such a manner as to form a trough, rounded in the 
interior, and of such dimensions as to allow the largest trees to 
lie, or to move along quite readily-. When the direction of the 
trough turns, or has any bending, of which there are many, its 
sides are made higher and stronger, especially on the convex 
side, or that from which it bends, so as to provide against the 
trees bolting or flying out, which they sometimes do, in spite of 
every precaution. In general, the trough is from five to six 
feet wide at top, and from three to four in depth, varying, how- 
ever, in different places, according to circumstances. 
