456 THE UNIVERSE. 



The secretion of the perfume is usually continuous, be- 

 ginning at the time the flower opens, and ceasing when it 

 fades. Even when the corolla, being altogether ephem- 

 eral, only lives for a few minutes, it is still observed to per- 

 fume the air during these brief moments. This is seen in 

 the magnificent Cactus grandiflorus. Quite inodorous a 

 few instants before it blows, it discharges a scented cloud 

 when, towards twilight, its calyx opens ; but the enchant- 

 ment vanishes before midnight, with the death and decom- 

 position of the flower. 



Some flowers of nocturnal habits, which do not disdain to 

 lend life to the night, shed their perfumes only during the 

 darkness; these are the bats of the vegetable kingdom. 

 Their sombre mournful hue has often led botanists to sad- 

 dle them with unpleasing names ; tristis or nocturnus is the 



first time in the works of Avicenna. The Orientals, in the times which preceded 

 ours, employed it with extraordinary profusion. Some historians assert that when 

 Saladin took Jerusalem, in 1188, he caused the interior of Omar's mosque to be 

 washed with rose-water, and for this purpose it was employed in such quantities 

 that Father Sanut relates that 500 camels were employed to bring it from Damas- 

 cus. Mahomet II. also, after the taking of Constantinople, ordered St. Sophia to 

 be washed in the same way. According to Father Catrou's account, the Princess 

 Nourmahal surpassed both, for she collected sufficient rose-water to fill a canal, 

 on which was launched a bark, which bore her, accompanied by the Great Mogul. 

 Indeed, it was during this remarkable trip that the essence of rose was discovered, 

 having formed at the surface of the artificial lake owing to evaporation caused by 

 the sun. 



The essential oil of roses is one of the most exquisite and dearest perfumes, and 

 justly bears the title of attar, or sweetest of fragrances. About 100 pounds of 

 flowers are requisite to obtain nine to twelve drachms (avoirdupois) of this oil, 

 which comes to us from the East and India, and which is often called butter of 

 roses. Hippocrates and Galon were acquainted with this product, and often em- 

 ployed it in medicine; nowadays it is only employed to perfume linen and rooms. 



