486 



SCIENTIFIC NE^A^S. 



[May 25, iS 



Ascension to 3h. 39m. 30s., crossing amongst other 

 stars numbers 91 and 120 in Bessel's catalogue ; the other 

 is in 23° 55' N. Dec, and appears to reach from R. A. 

 jh. 39m. 40s. to R. A. 3.h. 42m. 10s., apparently uniting 

 together seven stars. 



The map of this region of the sky, made in 1886, 

 contained 1,421 stars, the smallest being of the i6th 

 magnitude; the present map contains 2,326 stars, the 

 smallest being of the i8th magnitude. This shows how 

 g]-eatly the sensitiveness of the plates has been 

 augmented by the attention bestowed upon them. 



With longer exposures other details might, perchance, 

 be secured, but at the Paris Observatory the reflected 

 glare from the lamps of the city tends to fog the plate, if 

 the exposure exceeds four hours. In consequence, 

 Admiral Mouchez, the director, is endeavouring to 

 obtain funds to erect a branch establishment at a 

 little distance from Paris. 



MULBERRY TREES. 



'T'RAVELIERS in the south of France, who are also 

 familiar with the scenery in China, have been 

 struck by a curious resemblance between the two land- 

 scapes. The cause of this similarity may not be at 

 once apparent ; but the resemblance is produced by the 

 appearance of the mulberry trees which are grown for 

 the silk industry. The Chinese discovered, after 

 centuries of experience, that a certain height produced 

 the best results. The trees are kept to a height not 

 exceeding ten or eleven feet ; this has been found to 

 yield the best crops of leaves, and at the same time 

 affords facilities for gathering them from the branches by 

 means of ladders. When the first silkworms were 

 smuggled from China by two Jesuits in the sixth 

 century, the eggs being hidden in a cane, they brought 

 with them to Constantinople, not only the silkworms, but 

 the complete knowledge of the art of rearing them, and 

 the treatment of the silken produce. The mulberry 

 tree was cultivated in France, in 1564, for this purpose, 

 and not only is its leaf peculiarly adapted as food for 

 the silkworm, but the tree is able to withstand a treat- 

 ment under which few others would continue to flourish. 

 Two crops of leaves are gathered at intervals of a few 

 weeks, and the vitality of the tree is such that a third 

 crop is put forth. This third supply is left on the tree 

 for the natural purpose of sustaining its growth ; but 

 the frugal proprietors, though they dare not deprive the 

 tree for the third time in one season of its organs of 

 respiration, will not permit them to be wasted, and 

 about a week or ten days before they would naturally 

 have dropped off, after having fulfilled their functions, 

 they are gathered for the third time, just as soon as they 

 have ceased to be of use to the tree, but before they have 

 withered. The leaves are gathered in baskets of a large 

 size, and are used as fodder for the cattle, who relish 

 them very much. It would seem that the leaves of 

 some of our trees might be put to the same use, for the 

 cattle eagerly crop the lower leaves of many kinds of 

 trees, and at present they are invariably allowed to drop 

 ojf to form a very poor manure. 



Earthquake in Madagascar. — A correspondent of 

 Cosmos, writing from Tananarive, announces earthquake 

 shocks at that town on March 17th, about 8.47 a.m. The 

 weather had been very wet for the three weeks pre- 

 ceeding, the rainfall having exceeded 9 ins. 



DISINFECTION. 



The Disinfection of Rooms. 



A CONTRIBUTION to our knowledge of efficient 

 disinfection has been made by Dr. S. E. Crupin, 

 of the Alexander Barracks Hospital, St. Petersburg 

 (Zeitschrift f. Hygiene 3, Bd., 2 heft, 1887). 



He used chlorine gas for purposes of disinfection with 

 apparent success until the following incidents occurred, 

 which caused doubts as to its efficacy. 



A ward infected with diphtheria, of 900 cubic metres 

 capacity, was disinfected with chlorine gas evolved from 

 the reaction of 50 kilos of chloride of lime and 65 kilos ot 

 hydrochloric acid ; the ward was well ventilated, and not 

 occupied for seven months. It was then used for the re- 

 ception of measles for four months. Some of the cases 

 began to show diphtheritic complications ; the ward was 

 therefore closed and disinfected with chlorine gas, using 

 to each cubic metre 150 grms. of chloride of lime and 

 165 grms. of hydrochloric acid. It was disused for seven 

 months, and then opened for the reception of small-pox 

 cases ; again diphtheria showed itself, the ward physician, 

 two sisters, and a servant being among those struck 

 down. For the third time the ward was closed and dis- 

 infected with chlorine ; it was opened again after a tew 

 months, and there had been no return. 



Laboratory experiments have shown the efficacy ot 

 chlorine, but Dr. Crupin thought that the conditions of a 

 laboratory experiment, perhaps, could not be observed in 

 actual practice. To ascertain this he exposed anthrax 

 spores on threads in a ward, and evolved chlorine gas 

 from one kilo of chloride of lime per cubic metre. Upon 

 after-cultivation of the spores, out of seven threads ex- 

 posed in different parts, the majority were found not to 

 be disinfected at all. He therefore forsook chlorine and 

 experimented with the following solutions : — 



1 . Corrosive sublimate solution, one per thousand. 



2. Carbolic acid solution, five per cent. 



3. Equal volumes of both the above. 

 Experimenting on anthrax spores, he found that the 



carbolic acid solution failed, that the corrosive sublimate 

 disinfected in the majority of instances, but by far the 

 best result was obtained with the mixture. He therefore 

 advises for the disinfection of rooms, washing and spray- 

 ing with equal volumes of one per thousand, corrosive 

 sublimate solution and a five per cent, solution of car- 

 bolic acid. According to his experience, rooms thus dis- 

 infected are not injurious to their subsequent inhabitants. 

 It is noteworthy that he disinfects after pneumonia. — 

 Public Health. 



Pre-Historic Monuments. — The French Government 

 is giving great attention to the preservation of the 

 cromlechs or dolmens, and menhirs of Morbihan. A 

 commission acting under the Minister of Public Instruc- 

 tion is charged with acquiring them on behalf of the 

 nation. 



The Zones of Thibet. — According to General S. J. 

 Walker (Proceedings Royal Geological Society) Thibet may 

 be divided into three zones, rising from south to north.; 

 The most southern, 10,000 to 12,000 feet above sea level, 

 contains all the towns and villages of the settled popula- 

 tion. The middle zone, 12,000 to 14,500 feet high, in- 

 cludes the pasture-lands of the nomadic Bodpas. The 

 northern zone, 14,000 to 17,000 feet in height, is par- 

 tially occupied by Turkic and Mongol nomads, but is 

 mostly abandoned to wild animals. 



