Survey of the Northwestern Boundary of the United States, 1857-1861, Band 8,Ausgabe 174

U.S. Government Printing Office, 1900 - 78 Seiten

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Seite 73 - Majesty shall be continued westward along the said forty-ninth parallel of north latitude to the middle of the channel which separates the continent from Vancouver's Island, and thence southerly through the middle of the said channel, and of Fuca's Straits to the Pacific Ocean...
Seite 73 - From the point on the forty-ninth parallel of north latitude, where the boundary laid down in existing Treaties and Conventions between Great Britain and the United States terminates, the line of boundary between the territories of Her Britannic Majesty and those of the United States shall be continued westward along the said forty-ninth parallel of north latitude...
Seite 67 - Almost invariably a small precipitate soon shows itself, which, if fine grained and nonadherent to the glass, may be regarded as pure calcium oxalate; otherwise it contains, or may largely consist of, magnesium oxalate. It is in that case to be collected, ignited, redissolved, and reprecipitated.
Seite 35 - This involves the omission of the "hygroscopic" water from the list of constituents, which would be eminently proper were it always possible to be sure that the loss at 100° to 110° truly represents mechanically held water. Since it very often represents more, and the determination as to whether or not it does in each case is not always possible and would add to the time required for the analysis, it seems necessary to include this water. What errors may arise from its exclusion the following rather...
Seite 74 - A single solution of the ignited barium sulphate in concentrated sulphuric acid and reprecipitation by water suffices to remove traces of calcium which might contaminate it if the rock was one rich in calcium, and even strontium is seldom retained by it in quantity sufficient to give concern.
Seite 106 - The error involved in the above estimation of the sulphur of soluble sulphides, due to the possible reducing effect of hydrogen sulphide on ferric salts, is probably negligible. Most of the hydrogen sulphide would be expelled before any such action could take place and probably before the ferric salts were largely attacked, but of course the small proportion of sulphur set free as such from, pyrrhotite would escape estimation and introduce further uncertainty. In general, it would be safe enough...
Seite 35 - Friedel ° indicates a means for determining the true weight of water lost by minerals behaving like the zeolites, even without collecting the water lost, namely, by driving out of the dehydrated and weighed mineral, under proper precautions, any air it may have absorbed in the process of drying and cooling, and collecting and measuring this air and thus finding its weight, which, added to the apparent loss, gives the true contents in water.
Seite 53 - This appearance is possibly due to zirconium with the phosphorus and titanium,2 and is so unusual and striking that it is worth while calling attention to it. With basic rocks very rich in titanium and phosphorus the residue may amount to 2 or even 3 per cent of the rock. The subsequent precipitate of alumina, etc., is usually ignited in the crucible containing the residue from the silica. It might be supposed that this residue would contain most of the barium of those rocks carrying that element,...
Seite 41 - Fig. 15, which hardly needs detailed description, shows it in a modified form, which differs from the original forms of Gooch in that the tubes for connecting with both the drying and absorption vessels are constructed wholly of platinum instead of lead glass. The form of apparatus depicted in fig.
Seite 15 - The specimens were taken and analyzed at widely separated times and by different persons, it is true, but they were unquestionably from the same rock mass, in which, however much the relative proportions of the different mineral constituents might vary within certain limits, there can be no reason to doubt the general distribution of all the elements shown by the second analysis.

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