In fact a very large proportion of these fragrant sweet-smelling substances, Myrrh, Cassia, Bdellium, etc., come from these sunny Eastern lands, which are not exactly deserts but very close to them. Manna, e.g., is obtained from the flowering Ash (_Fraxinus ormus_) in Sicily by transverse incisions being made in the bark, so that the brownish or yellowish viscid juice exudes and hardens on the wound. _Ladanum_ is a varnish or gluey coating found on the leaves of _Cistus creticus_, which grows in Crete. In old times the glue was collected from the beards of the goats which had been browsing on the plant. Although this method, no doubt, increased the strength of the perfume, it has been abandoned, and the ladanum is obtained by a "kind of rake with a double row of long leathern straps." The straps take the glue from the leaves. It is used as a perfume in Turkey. Another very interesting Eastern plant sometimes seen in old-fashioned country gardens in Britain is the "Burning-bush" (_Dictamnus fraxinella_). Like a great many of these half-desert plants, it is full of an acrid, ethereal, odorous substance. On a calm, hot summer's day, this material exudes from the leaves and surrounds the plant with an invisible vaporous atmosphere. Such an atmosphere probably assists in preventing the water from evaporating or being transpired from the leaves.[52] [52] This was suggested by Tyndall, but has been denied by others. Now if one places a lighted match a little below the leaves or flowers this vapour catches fire, and there is a display of flames and smoke with little explosions, followed by a strong smell. The plant may be injured if it is set on fire too frequently, but generally does not seem to be any the worse for the experiment. The Mediterranean is the home of the Myrtle and Olive, of Oranges and Lemons, of Figs and Vines, of Almonds and Raisins, as well as of many other important and interesting plants. The olive crop in Italy yields about ninety millions of gallons of olive-oil every year. The olives are collected as soon as they become ripe, and are crushed in circular stone troughs with a perpendicular millstone. The paste is then pressed in bags and afterwards clarified by passing through cotton wool.[53] To the eye of a foreigner the white gnarled stems and silver-green foliage of the olive groves are not particularly attractive. [53] _Journal Society of Arts_, August, 1896. Near Burriana, in Spain, one may walk for miles through the plantations of oranges. The dark-green glossy leaves and golden fruit of the orange make a most beautiful contrast, but the dry, thirsty soil, and the careful way in which the water is regulated and supplied by small gutters, most jealously watched over, make the tourist realize the difficulty of agriculture in so dry and arid a country.