, 1877-02-24

In response to an invitation extended
,omc week, ago by the Portland Board
Of Trade. Col John VI. Wilson, chief en-
ginror OF the Thirteenth Lighthouse
District. delivered a very able and care
mlly prepared address before that body
m.t evening. As previously announced
tic subject of Col Wilson's address was,
"Thc Improvement OF the Lower villa
mc,tc and Columbia Rivers" \ num-
her of invitation tickets were issued to
,hc prominent merchants, business and
professional gentlemen Of Portland, and
the board room was crowded to over
flowing, all eager to hear the opinions
and suggestions Of 50 thorough and com.
pctent AN engineer as Colonel Wilson on
the vltu!ly important subject Of the i'm
provemcnt of the Lower Willamette and
Columbia rivers.
1t hping the regular monthly meeting
of the board the audience was called to
order by Hon. II. W. Corhctt, president.
The minutes of the last regular meet.
ing were read and approved.
On motion. further business was dis.
pcnsed with III order to enable the board
and those invited an opportunity to
hear the address.
COL. WILSON
Was then introduced by the president
and proceeded to address those present
for about forty minutes.
Col. Wilson'S paper referred to the
subject of the improvement Of tidal riv-
ers, the operations upon the Clyde and
the proposed improvement Of the Lower
Willamette and Columbia.
lie commenced by claiming that he
was neither an orator nor lecturer, but
simply an engineer and soldier, and that
he would place hefort the Board ofTrade
II simple statement Of facts.
Beginning with the subject of the gen
oral improvement Of tidal rivers, he gave
the three divisions of u tidal river as
stated by the celebrated engineer Steven
son, and announced that the lower Viii
lOuIette and Columbia, where trouble oc-
ours, belong to the second section, name
ly, "the tidal compartment" where the
phenomena Of ebbing and flowing is OBJ
served, the continuance of low water
stand being gradually protracted as we
proceed upwards, until the existence OF
tide is unknown.
He then referred to the necessity OF
having n complete and elaborate survey,
with all possible data, before preparing a
plan oil improvement, and stated that III
tidal rivers the problem to be solved was
TO SO graduate the velocity as to give nc
greater securing force to the water after
the channel is opened ut one point thar
to another, to SO open the channel and
lead up the tide that the difference o
rise ut the two extreme points, the diff
ference between the time of high waite
at those places and the period Of low
water stand should he the least possible
lie then denounced the fallacious phl
Of wingdams for tidal river, showing
the damage duue by them on the Clyd
and ON the Hudson, and claiming tina
by increasing velocity around their end
they formed the river into series o
holes and bars.
lie announced the great principle t.
he that of non interference with tides t
tAeir dctriment, and went ON to shoV
how they should le led up, and to emu
.nerute the obstacles which are hindran
ces to their rise.
The work to bc done, he said. consist
ed in the removal Of all obstacles to tn
upward flow of tide in the shape {
rocks, bars, etc, the baildIng Of dams {
such shape and height ms should in
crease tPe velocity only sufficient to kee
open the channel, and which should gen
rs lead the currant in the proper direC
Son, the revetmrut Of shores at place
where the material is gradually washin
assay aud forming bars below. and til
ca,ing OF such subsidiary channels 4
Gerry oil too much OF the volume iror
tie mpin channel.
Col. Wilson then discussed the suhicC
~ the necessary contraction Of the rive