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THE AUSTRALASIAN JOURNAL OF PHARMACY. 
earth, is a heavy solid, surrounded by a liquid zone of basic rock (trachytic) ; 
then by an outer layer of a lighter and acid rock (basaltic) ; the whole enclosed 
by a crust, the wrinkles on whose surface are mountains. 
In very ancient times (Laurentian) the Atlantic Ocean was supported on a 
floor of gneiss, or of some rock which became gneissose. As the earth cooled 
it contracted ; this shrinkage led to the folding and crushing of parts of the 
crust. In those early Laurentian days the earth's wrinkles rose above the 
surface in broad belts, foreshadowing the positions of the mountain ranges of 
Western Europe and Eastern America. Various denudating agents then carved 
out these old crystalline rocks, whose detritus, piled along the margins of the 
Atlantic, formed the stratified deposits of Paleozoic times. Sir J. Wm. Dawson 
thinks that too much is ascribed to the action of vast continental glaciers ; he 
thinks that masses of floating ice are more probable agents for many of the 
phenomena said to be due to continental glaciers, and that moraines are the 
debris of ice-drifts during a period of great submergence. 
The Atlantic is in about the same position now that it always has been. 
At one period it has overspread areas that are now continental ; at another 
period it has been contracted within more narrow boundaries by the elevation of 
marginal land. Thus, in the age of the Coal measures swampy flats extended 
into the shallow parts of the Atlantic ; whereas in the Chalk age it is probable 
that the American continent stretched out farther seawards than it does now. 
Finally, Sir William is of opinion that Europe and America were probably 
connected by Greenland, Lapland, the Faroes, &c. In these Arctic regions was 
the pre-Cambrian land which furnished the sediments whose partial metamorphosii 
supplied the upper Laurentian and Huronian formations. 
Quick Boiling. 
Mr. T. Fletcher, of Warrington, England, has given an account, before the 
Gas Institute of London, of some successful experiments in modifying the usual 
plane surfaces of pans, boilers, &c., so as to heat water quicker than hitherto. 
When a flat-bottomed pan of cold water is set on a gas flame, there is a large 
surface of the pan bottom which is not heated by the gas, because there is a film 
of unburnt gases preventing contact between the flame and the metal of the 
pan bottom. This may be proved by pasting a piece of paper on the pan 
bottom, and it will remain uncharred, showing that the pan bottom and the 
flame at that part are not heated to 4.00° F. Mr. Fletcher proposes to corrugate 
the outer surfaces of the bottoms of pans and kettles, &c., as he finds that with a 
series of projecting rods on the bottom of a kettle he could boil the same 
quantity of water in half the time that a flat-bottomed kettle required. This 
is due to the projections, corrugations, or rods becoming so hot as to be in 
contact with the flame , and so more heat is conveyed in a shorter time to the 
water in the kettle. For large boilers, such as the Lancashire boiler, Mr. 
Fletcher has been experimentally successful in the use of longitudinal webs, 
rolled on to the boiler plates of the flues, and in the line of direction of the 
flame. 
Pipitzahoic Acid. 
History. — This substance was discovered by Professor Rio de la Loza and 
analysed by Weld. Subsequently Dr. Schaffner discovered the plant itself and 
named it. His specimens came into the possession of Mr. Vigener, a German 
pharmacist, who again drew attention to it. Its chemical investigation was then 
taken up by Messrs. Ausckiitz, Leather, and Mylius, whose researches are printed 
in the Journ. Chem. Soc. and the Berichte . 
Source. — Hitherto it has only been found in the roots of Trixis pipitzahuac— 
natural order, Composite® — a plant growing in Mexico. It is contained in large 
