Outer Zone Is Believed: The outer zone is believed to be liquid because it stops S waves (shearing earthquake waves), while the inner zone is believed to be solid because P (compres-sional) waves travel slightly faster there. The density changes from 12.3 to about 13.3g./cm3 at the boundary of outer and inner cores and increases to about 13.6g/cm3 at the centre of the earth, 6, 371km (3,956 miles) down.
Meteorites reaching the earth's surface provide clues as to its composition. Such meteorites are made either of stone or else are made predominantly of iron.
There are eleven hardiness zones, which are defined according to lowest winter temperatures. Zone 1 represents the coldest conditions, with winter temperatures below -50°F (-46°C); zone 11 is the warmest, wit] a minimum winter temperature of above 40°F (above 4°C). The classification of a plant into a particular hardiness zone means that the plant will normally thrive in that zone and also in any zone which is marked with a higher number.See Also Zone Travel:Zone travel cards, purchasable at fixed rates for any class, permit holder to buy unlimited rail tickets at half price within various 201 (such as Normandy and/or Brittany, the Riviera and/or Upper Savi during a fixed period of time. A card valid for the whole of France also offered. Zone-card travel is for the indomitable goer, with enough to go.
Rail-and-motor-coach combination tickets are provided to stimuli inexpensive touring in the holiday regions served by SNCF coaches.
From this data he can obtain in his negative any one toni and will know exactly the tones that other subject lumi nances will produce. The infinite gradation of light an< shade found in nature Adams divides into ten zones Zone O is black, Zone IX is white. Between these ex tremes are eight tones of gray, Zone V being the "middle tone—not by objective measurement, but by subjectivi judgment—and next to it, marked VI, the value tha conveys to the photographer the feeling of the tone o average, well-lighted skin.
On The Other Hand See Succeeds In Zone:C. goulimyi has 4-inch-high globular flowers of pale to deep purple and according to bulb broker Ken McClure, was introduced to gardens by C. N. Goulimis, who found it growing wild in southern Greece in 1954. It only succeeds in Zone 9, where soils never freeze, but is included in this plan to tempt the palate of a southern gar¬dener.
C. Kotschyanus is a pale rose-lilac, and is originally from the mountains of southern Turkey. It reaches 4 inches in height and blooms in late September and October. It is hardy from Zone 5 south.
C. laevigatus 'Fontenayi' is the latest blooming autumn crocus, choosing to flower in December. The leaves emerge with the blos¬soms. Color is lavender feathered with purple, and the flowers exude a delightful scent reminiscent of freesias. Height is 2 1/2 inches and corms are hardy from Zone 6 south. If you are in an area where winters are early but not too cold, try this plant in a sheltered spot.
Gutenberg found that abnormally low velocities of seismic waves occur in a zone centered at about 62-124 mi (100-200 km) be¬low the surface. In this low-velocity zone the mantle transmits earthquake waves more slowly because it is close to its melting point and therefore less rigid than usual. A few years after this discovery Sir Harold Jeffreys of Cambridge University and K. E. Sullen of Sydney, Austr., discovered that between the depths of 210 and about 380 mi (338 and about 612 km) there is a rapid change in density—a transition zone in which the density suddenly increases by 20%.
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