Mineralogy and Geology. 395 
our own Coast Survey has ever been reproduced in a pomeiey’ 
form for our shores from the St. Croix to the Chesapea e 
construction of the map was intrusted to Mr. Robert Base. 
formerly of the British Ordnance Survey, and now chief topog- 
rapher to the Survey of Canada. It has been engraved on steel by 
Ramboz and Jacobs of Paris, under the su ensiondens of Mr. 
Gustave agora and is remarkable - the beauty of its execu- 
125 miles to the inch, which is a reduction of that now before us, 
and bears the date of 1864. Changes = acpi to the geolo- 
y have, however, been made in the lar map, on which it has 
been possible also to give the s sbdiyisiard of the Quebec group a 
Eastern Canada, which the small scale of the first map did no 
low. 
The present map is on the scale of twenty-five miles to the inch, 
and measures eight feet from east to west by three and a half 
feet from north to south; extending southward to latitude 37°, and 
westward to longitude 100°. Its northern limits include Pe lakes 
Manitoba and Winnipeg, James’s Bay, N ewfoundland, and the ad- 
jacent Labrador coast, while to the south it takes in "Kensas and 
northern Virginia. 
The geological subdivisions adopted on this map are—l1. Lauren- 
tian, 2. Labradorian (or Upper Laurentian), 3. Huronian; while for 
New ¥ York sur- 
inion, 15. Gu ae 16. pe ars or Salina, 17. Lower Helder- 
berg, 18, Corniferous and Oriskany, 19. Hamilton, 20. Chemung — 
and Portage, 21. Old pein sandstone, 22. Lower pipeaaae® in, 
limestone, 23. Bonavent 70 SOL eet 24. Coal patio os 25. 
Upper Carboniferous Soeees , 26. Permian, 27. Trias Cre- 
taceous, 29, Tertiary. In 1 e eas astern basin, as is well knowns the 
geological survey of C 
which is regarded as nee of the Caleierous — Chazy for 
scen: ating. ¢ order, viz: 
mations ane sijyidied into three parts 
pel inet re represente: 
sap vis being colored like the Caleifer- 
while ee Lanzon (6), is distin- 
dd to this two colors for intrusive 
ae one for granites and th do 
we have not less t 
