276 THE REPOSE OR SLEEP OP PLAKTS. 



structure as the largest. Mr. Hazard, the jjatentee, lias published a 

 small pamphlet containing observations upon the system, descriptions, 

 and numerous testimonials of approval. In his remarks on the source 

 of heating, which is illustrated by an engraving, he states, — " A is the 

 fire-box, lined with brick, in order to prevent the fire acting imme- 

 diately on the iron (pipes), so as to injure the surrounding; the heated 

 gases and smoke are then distributed into a series of tubes, and con- 

 tinues to wind its way until it enters the chimney. The outer atmo- 

 sphere is brought from without by means of an air-drain, enters the 

 chamber below the pipes, and in its ujjward progress is arrested by the 

 first row of heated tubes, which, being hotter than the others, are con- 

 siderably lessened in temperature by their receiving the first rush of 

 cold air ; it then passes upwards, and over the external surface of the 

 upper rows of tubes, until the chamber becomes, with one uniformly- 

 heated atmosphere, of a genial and healthy nature, ready to be con- 

 veyed into the various apartments requiring warmth. The best fuel is 

 coke, or the AVelsh stone-coal, known by the name of anthracite. 

 Either of these, with cinders from a common fire, to prevent the other 

 from burning with too great energy, will be found the cheapest of all 

 firing." We liave extended our remarks beyond what we intended, 

 but we are confident the system merits all we liave said in approval, 

 and with confidence in its utility, and economy in its construction and 

 working, we recommend it to our readers. — Conductok. 



THE REPOSE OR SLEEP OF PLANTS. 



BY SENEX. 



The alternate state of activity and rest, which appears to be necessary 

 to maintain the body in health and the mind in vigour, is not confined 

 merely to sentient beings, but pervades the whole economy of nature, 

 whether animate or inanimate. The term sleep (a state of rest), as 

 applied to the vegetable kingdom, is used to express a peculiar state of 

 many plants during the nigiit, evinced by a change in the position, 

 generally a drooping or folding together of their leaves or leaflets. 

 The instances of this state of rest are constantly before our eyes. The 

 Lupin drops listlessly the slender fingers of its leaves at dusk, as if to 

 repose from its daily labour. The Four-o'Clock (Convolvulus minor) 

 closes its blue eyelid betimes in the evening, and opens it again as soon 

 as the sun is well above the horizon. In some plants the leaves ap- 

 proach the stem quite close. 



Linngeus, speaking of this condition of plants, traces the analogous 

 properties possessed by the subjects which compose the animal kingdom 

 when under the influence of sleep or inactivity. The monkey rests on 

 its side, the camel with its head between the fore-legs, and many birds 

 cover their heads with the wing; so, he remarks, the leaves of plants 

 assume different positions during the night. The object in general 

 appears to be the protection of some more delicate part of their struc- 

 ture from the eft'ects of tiie night air. Some bend downwards over 



