P OP ULAR MIS CELL ANY. 



859 



Virtnes of Mountain Air. It maybe re- 

 ceived as proved that mountain air is good 

 in cases of consumption. Why it is so, may 

 be explained by reference to the qualities 

 of the air of great altitudes, among the most 

 conspicuous of which are its purity, its rare- 

 faction, and its coldness. All modern ob- 

 servers, says the " Lancet," are agreed that 

 pure air is the most essential recmisite in 

 the treatment of the scourge. Pure air is 

 not to be found near the great centers of 

 human population, nor even in ordinary 

 lowland country. To obtain it in perfection 

 we must look to the ocean, the desert, or to 

 great altitudes. In these three localities we 

 are far removed from the ordinary sources 

 of atmospheric contamination, and it is 

 hardly necessary to seek to assign any pre- 

 cedence among them, as in each case the 

 atmospheric purity is practically absolute. 

 The next and most essential characteristic of 

 the air, at great altitudes, is its rarefaction, 

 by virtue of which it provokes deep and full 

 respirations, thus promoting pulmonary ex- 

 pansion, and affording a favorable condition 

 for the absorption of morbid deposits. It 

 was long believed that rarefied air tended to 

 promote haemorrhage, and the well-authen- 

 ticated stories of the sufferings of mount- 

 aineers from epistaxis and inelama, seemed 

 to confirm the belief: But it was forgotten, 

 when these stories were brought forward, 

 that the conditions of blood-pressure at the 

 various orifices are different from those 

 which prevail in the internal organs. The 

 congestion at the surface of the body* must 

 be accompanied by a proportionate anaomia 

 of the deep-seated parts, and among them 

 of the lungs. Hence, rarefaction of the 

 air, so far from being injurious in cases of 

 pulmonary haemorrhage, affords a means 

 for its arrest and relief. Cold is now known 

 to be at least not unfavorable in phthisis. 

 The air at great altitudes is not only very 

 cold, but also very dry ; and this combina- 

 tion of conditions tends to correct unhealthy 

 secretions, while it is, at the same time, pro- 

 motive of appetite and physical activity. 

 This point is one of great magnitude. 



Clothes-Moths. Clothes-moths, injuri- 

 ous to woolen goods and furs, are of the 

 species of Tinea pellionella, biselliella, tapct- 

 zella, or rustica. The most common one is 



Tinea pell ionella, which in its mature state 

 carries about half an inch expanse of wings. 

 Its fore-wings are shining, grayish-yellow, 

 with three indistinct brownish spots in the 

 middle, and its hind-wings are whitish-gray. 

 It is abundant in houses, and may be found 

 at any time between January and October, 

 though most abundantly in the early sum- 

 mer months. The moth is innocent. The 

 larva, which does all the damage, is a tiny 

 caterpillar, dull whitish,with a reddish-brown 

 head. It is the only one of the four species 

 that makes a tunic or movable case for 

 itself. This case is very ingeniously con- 

 structed, and consists of an outer layer of 

 fragments of the articles it has fed upon, 

 and an inner layer of silk, forming a soft 

 and smooth lining. It is nearly cylindrical 

 in form, but of slightly larger diameter 

 across the middle, and a little flattened 

 above, and it is open at both ends. These 

 cases are varied in their appearance, and of 

 different colors, according to the color of 

 the goods from which they are formed. The 

 case is enlarged as the insect grows, both 

 by adding to its length and to its circum- 

 ference. For the latter enlargement, the 

 case is split and patched up in two slits at 

 each end, with an ingenuity that borders on 

 intelligence. The chrysalis state is assumed 

 inside of the case, the caterpillar becoming, 

 by throwing off its last larval skin, a little, 

 yellowish-brown, helpless thing, similar in 

 form to the chrysalides of the larger moths. 

 The chrysalis is anchored by fine threads to 

 the cloth in which the insect lives. From 

 this the perfect insect emerges, when its 

 time has been fulfilled, lays its eggs, and 

 then dies. The eggs are extremely minute, 

 and are deposited on the cloth, or in crev- 

 ices and corners close to a supply of food. 

 The young grubs begin life by attacking 

 the old cases of their progenitors, with 

 which they make cases for themselves, and 

 begin to feed on cloths proper at a later 

 period of life. 



Polished Objects of Silieified Wood. 



Mr. George F. Kunz, in exhibiting before 

 the American Association polished speci- 

 mens of jasperized and agatized woods from 

 Arizona, referred to the description of these 

 woods which he had published in the "Month- 

 ly" for March, 1886, their magnificent 



