108 
River. The district thus included lies along latitude 
45° 50/, between longitudes 76° 40’ and 77° 40’; the 
town of Pembroke being 77° 10’, with an elevation 
above sea-level of 423 feet. At the upper end of the 
district the Ottawa divides its waters, and encircles 
the large Allumette Island; the Culbute Channel on 
the north being narrow, while the southern one ex- 
pands so as to be known as the Upper and Lower AI- 
lumette Lakes. On the Quebec shore the land rises 
precipitously; the Laurentian Mountains seldom re- 
ceding more than a mile, and at times rising sheer 
from the water’s edge in towering cliffs of trap. On 
the Ontario side the land is comparatively undulat- 
ing, and rises by a succession of plateaus separated 
by ridges of rock, or by ranges of hills gradually in- 
creasing in height. After a graphic description of the 
beauties of this district, the writer outlined the princi- 
pal sand-plains which constitute a large portion of the 
steppes of the southern shore, and pointed out that 
their levels coincided with the well-marked terraces 
found on Allumette Island and at other points along 
the river. The formation of these sand-plains was 
then fully discussed ; and it was claimed that they had 
undoubtedly been formed from the débris transported 
by flowing water from the rock ranges that bound 
and intersect them, and toward which the surface ~ 
gradually changes from fine sand (or occasionally 
clay), through coarser sands, pebbles, etc., to bowlders. 
The principal plain is that called the Chalk-river 
sand-plain, extending from near Pembroke, twenty 
miles westward. It is interrupted toward the lower 
end by broken ridges, which harmonize in position 
with the rapids, and which formed parts of barriers 
between a higher level westward and a lower level 
eastward. Occasional sand-ridges occur, which lie be- 
tween the ancient mouths of rivers, of which some are 
now extinct, and others, as the Petawawa and Musk- 
rat, still flow in greatly diminished volume. The 
two principal levels of this plain correspond with two 
terraces boldly marked on the Laurentians near the 
head of Coulonge Lake, fully thirty miles away. A 
lake as large as, or larger than, Superior must in the 
past have hidden in its great depths Allumette Island, 
the entire Pembroke district, and adjacent sand- 
plains, as well as thousands of the now arable acres 
lying toward Renfrew. As indicated by the ter- 
races, there had been two distinct periods, in the 
first of which the water had been 200 feet deeper, and 
in the second 100 feet deeper, than the present level. 
After describing the constitution of the soils derived 
respectively from the granite or trap ridges, and their 
SCIENCE. 
relative capacities for agriculture, the writer very 
lucidly and interestingly explained the changes, as 
witnessed by him, which are still going on in the 
district, and the manner in which, by the incessant 
weathering and denudation of the rocks, sand-plains 
on a smaller scale are still being formed. The pres- 
ent barriers which cause the rapids interrupting navi- 
gation were explained to be of varying degrees of 
hardness, so that change proceeds more rapidly at 
certain points. 
sandstones (Potsdam) compacted with bluish clay, 
and are being rapidly eroded; and at a not excessively 
remote date the channel will be so lowered that the 
upper and lower lakes will form one navigable level, 
while the channel to the west, having a much harder 
bed-rock, will be changed to impassable rapids by the 
subsidence of the lake below them. Reference was 
made to various older channels which evidenced 
former higher levels which the existence of terraces 
and undoubted water-lines fully confirmed. In the 
discussion that ensued, several members who had 
visited the locality and other portions of the Upper 
Ottawa gave evidence as to the existence of numer- 
ous traces of old water-currents at points now much 
above the present levels. 
Mr. H. M. Ami presented a list of the Cambro-silu- 
rian fossils of the neighborhood, containing 228 spe- 
cies, and prefaced by a few notes as to its compilation. 
The report of the geological section on the summer’s 
work was also read, and the president announced that 
classes in botany and zoology would be held weekly. 
Franklin institute, Philadelphia, 
Jan. 16. — The annual report of Board of managers 
exhibited the addition of a hundred and thirty-nine 
new members during 1883, and of over three thou- 
sand volumes to the library. Preparations for the 
Electrical exhibition, to be held during the autumn 
of 1884, are in an advanced state. A national con- 
ference of electricians is in contemplation. 
ject of a ‘‘Proposed ordinance for the examination 
of steam-engineers’’ was warmly debated, pro and 
con, but no decisive action was taken. Mr. S. Lloyd 
Wiegand read a paper defending the use of cast iron 
in the construction of steam-boilers, it having been 
alleged by Nystrom and others that steam-boilers 
with flat cast-iron heads were dangerous. The secre- 
tary’s report embraced a summary of engineering and 
industrial progress for the past year. 
INTELLIGENCE FROM AMERICAN SCIENTIFIC STATIONS. 
The U.S. naval observatory, 
Vice-Admiral Stephen C. Rowan was appointed 
July 1, 1882, to succeed Rear-Admiral John Rodgers 
as superintendent of the observatory. On May 1, 
1883, Vice-Admiral Rowan was relieved by Rear- 
Admiral R. W. Shufeldt. The report of Admiral 
Shufeldt to Commodore J. G. Walker, chief of bureau: 
of navigation, under date of Oct. 22, 1883, covers the 
work of the observatory for the past year. 
The personnel of the observatory is as‘follows:— — 
Rear-Admiral R. W. Shufeldt, superintendent; 
Commander W. T. Sampson, assistant to superintend- 
ent; lieutenants, Pendleton, Moore, Bowman, Gar- 
[Vou. III, No. 51. 
Thus the channel rocks at the foot | 
of the river-reach in question are composed of fine © 
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