55o 



SCIENTIFIC NEWS. 



[Nov. 30, 1? 



From the foregoing it will be readily understood that as 

 soon as the temperature of the room in which the sprinkler 

 is placed is high enough to melt the solder joint, the 

 valve is opened by the pressure of water in the pipe, and 

 the sprinkler is at once in full operation. The sensitive- 

 ness of its action has been tried in many ways, and it has 

 been proved beyond doubt. 



In buildings which are not artificially heated, and in 



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Fig. 



-Sectional View of Grinneix's Sprinkler 

 in Action. 



which the water in the pipes might freeze, the pipes are 

 kept charged with compressed air. In case of fire, when the 

 valves of the sprinklers open, the air instantly escapes, 

 and by an automatic arrangement it is at once followed 

 by water. In places where the town water supply 

 is intermittent, or does not give a pressure of 10 lbs. 

 per square inch, on the top floor, it is usual to provide 

 a tank high enough above the highest sprinkler to give 

 the pressure required. In many country districts there 

 is an overhead tank and an ordinary pump. Last, 

 but not least, is the automatic alarm gong which gives 

 warning immediately there is any escape of water in- 

 side the buildings where the sprinklers are. This 

 alarm gong is actuated by the flow of water set up when 

 there is an escape from any cause whatever, and its 

 action continues so long as the escape takes place. This 

 is a most useful adjunct, and is only second in import- 

 ance to the sprinkler itself. The agents in London for 

 the Grinnell system are Messrs. A. Ransome and Co., 

 Stanley Works, Chelsea. 



— ■f-^t^fi^+g-' — » 



CABBAGES. 



TT ERE and there along the south coast of England and 

 the Welsh coast we find a plant known as the sea- 

 cabbage {Brasska okracea). It grows in tolerable plenty 

 on the chalk cliffs of Dover, and is also recorded from 

 the Isle of Wight, Cornwall, South Wales, and Great 

 Orme's Head. It is about 20 inches high. The leaves 

 are large and jagged, covered with a blue-green bloom. 

 The stem is tough and woody. The flowers are of a 

 pale yellow colour, and are succeeded by pods. The 

 plant belongs to the order of Cruciferas, the same large 

 and important order which yields the turnip, radish, 

 mustard and water-cress. 



From this wild original (or possibly from it and one 



or more closely allied forms not easily distinguished) 

 have been derived the countless varieties of the 

 cultivated cabbage. Red cabbages, Brussels sprouts, 

 with their crowds of little leaf-buds, cauliflowers, with 

 their dense masses of imperfect flowers, brocolis, savoys, 

 and kohl-rabi, are all cultivated forms of the weedy 

 ragged sea-cabbage. In Jersey, Mr. Darwin tells us, a 

 cabbage-stalk has grown to the height of 16 feet, and 

 had its spring-shoots at the top occupied by a 

 magpie's nest, while the woody stems are often 10 or 

 12 feet long, and have been used as rafters and 

 walking-sticks. A cabbage-stalk fashioned into a 

 walking-stick may be seen in the Museum of Economic 

 Botany at Kew. The principal varieties were established 

 before botanical curiosity had been excited, and we can 

 only get chance bits of information as to the time and 

 place of their first appearance. Theophrastus knew of 

 three cabbages, Pliny of six. Regnier has collected 

 evidence that cabbages were cultivated by the Celts of 

 ancient Gaul. There is no hint that cabbages were 

 known to the ancient nations of the East, and De Candolle, 

 who has made laborious researches into the subject, 

 believes that the cultivated cabbage is of European origin. 



No more curious instance is on record of the 

 conspicuous changes which may be effected by long- 

 continued cultivation and selection. But the cabbage 

 has a more direct and more human interest than belongs 

 to any mere botanical curiosity. It is a factor of appre- 

 ciable weight in the early civilisation of Western Europe. 

 We can imagine some old European savage, wandering 

 dinnerless along the sea-shore, until at length he was 

 pressed by hunger to experiment upon unfamiliar plants. 

 That savages do thus gain knowledge at the risk of their 

 own lives we may infer from the well-known fact that 

 they are well acquainted with the properties of the 

 common plants of their own country, and can point out 

 which are poisonous, which useless, which good for food. 

 Our savage sees the tall, weedy sea-cabbage, and finding 

 nothing more tempting, he tries its flavour. There is a 

 slight pungency of taste, which raises misgivings, but no 

 ill-effects follow. Next day the sea-cabbage is again 

 resorted to, and in time becomes a regular article of food. 

 Presently some ingenious fellow — the Watt of his age — 

 saves himself the trouble of a daily journey to the shore 

 by transplanting a few cabbages to a patch of ground 

 near his cave. Years, perhaps centuries, later another 

 great advance is accomplished, and men begin to raise 

 the cabbage from seed. Gardens and fences follow. It 

 is no longer necessary to spend whole days seeking food, 

 and the man's hands are set free to make himself shoes, 

 and a coat, and a house. 



We have perhaps given to the cabbage some share of 

 the credit which rightfully belongs to barley or some 

 other nutritious plant, but there is no doubt that the 

 cabbage played a considerable part in the early civilisa- 

 tion of Western Europe. Cultivated plants and 

 domestic animals are the very foundation of primitive 

 society. As the plants grow more juicy, and the animals 

 more docile, man too rises to something higher than he 

 was. He becomes able to lead the life which pleases 

 him, and not that which is imposed by climate and the 

 wild productions of the soil. He learns by slow degrees 

 to shape his own circumtances and habits. But his 

 intellectual gifts and his social aptitudes cannot be 

 developed without certain simple natural resources. 

 Of these the chief are plants worth cultivation and 

 animals worth domestication. 



