NOTES. 



5H 



by their number (585), we find the mean 

 length of the shoots to be about two inches. 

 The average number of leaves on each inch 

 of a number of shoots, taken at random, 

 was 34, so that the total number of leaves 

 on these 585 shoots may be set down at 

 39,814. Assuming each leaf to be only one 

 inch in length — which is considerably under 

 the mark, even when all the small, undevel- 

 oped leaves are taken into consideration — 

 we should have for the leaves a length of 

 about 3,501 feet, so that, in round numbers, 

 we may say that, including the shoots and 

 leaves, the growth in length alone of this 

 very moderate-sized young tree, during this 

 season, has amounted to the prodigious 

 number of 3,600 feet ; and, if the shoots 

 and the leaves could all be placed end to 

 end in a continuous line, they would extend 

 considerably more than half a mile. 



Action of the Sand-blast. — At a recent 

 meeting of the British Microscopical Soci- 

 ety, Mr. Wenham exhibited a piece of glass 

 "ground" by the sand-blast process, which, 

 under the microscope, presented a very 

 different appearance from common ground 

 glass. It is found that the glass or other 

 material, worn away by the sand-blast, is 

 not ground away at all, but broken up by a 

 battering action, similar to that of leaden 

 bullets against a block of granite. Hence 

 it is that, although, by the usual grinding 

 process, ordinary sea-sand can make no im- 

 pression on corundum, a blast with a press- 

 ure of 300 pounds to the square inch will 

 perforate it in a short time. Nay, even the 

 diamond itself may thus be speedily worn 

 away. 



A polished glass surface, exposed for an 

 instant to the sand-blast, shows an aggrega- 

 tion of points of impact, from which scales 

 of fractured glass have broken away in an 

 irregular radial direction. It appears as if 

 a pellet of glass had been driven in by the 

 collision of the sand, and the wedge-like 

 action thus set up had driven away the sur- 

 rounding glass. All these spots, or inden- 

 tations, when tested by the polariscope, 

 show a colored halo round each, proving 

 that the glass surface is under strain and 

 ready to yield to further fracture. The ac- 

 tion, therefore, is not so much due to the 

 hardness of the striking particles as to the 



force and velocity of impact. This is suffi- 

 ciently great to destroy the cohesion of the 

 material operated upon. The external layer 

 is carried against the under stratum, and 

 the material is crushed and disintegrated 

 by a portion of its own body. 



NOTES. 



Dr. Charles P. Russell gives a tabu- 

 lated statement of the mortality of the vari- 

 ous States of the Union, from which we 

 borrow the following regarding the death- 

 rates of various cities : The highest death- 

 rate in 1872 was exhibited by Memphis, 

 where the deaths were 46.6 in each 1,000 

 inhabitants. Other cities followed in this 

 order : Savannah, 39.2 ; Vicksburg, 36.5 ; 

 Troy, 34; Hoboken, 32.9; New York, 

 32.7; Newark, 31.6; New Orleans, 30.6; 

 Boston, 30.5. The rate for Philadelphia 

 was only 26.1; Brooklyn, 28.1; St. Louis, 

 20.1; Chicago, 27.6; Baltimore, 25.1; Cin- 

 cinnati, 20.5; San Francisco, 17.2. This 

 compares not unfavorably with the mortuary 

 statistics of British cities, where the lowest 

 rate was 21.4 ; that of London, Bombay, 

 and Calcutta, show only 29.2 and 25, re- 

 spectively. The highest known death-rate 

 prevailed in Yalparaiso, Chili, 66.9. 



Inoculating the vine with pure essence 

 of Eucalyptus globulus is said to be an ef- 

 fectual remedy for the phylloxera or grape- 

 vine disease. The mode of applying the 

 remedy is this : a broad incision is made 

 through the bark at the neck of the vine, 

 in which a few drops of the essence are de- 

 posited by means of a small camel's-hair 

 brush. In about three days the phylloxera 

 insect entirely disappears, while the vine is 

 not in the least injured by the operation. 



The practice of ringing and tolling bells 

 by swinging the clapper or tongue violently 

 against the side of the bell while the latter 

 is stationary, is said to be a very frequent 

 cause of fracture. The bell itself should 

 always be in motion when struck by the 

 object that is intended to set it vibrating. 



Pine-leaves, says the Mining and Scien- 

 tific Press, are largely utilized in Europe. 

 They are converted into a kind of wool or 

 wadding, which is used for upholstery in- 

 stead of hair. A kind of flannel is also 

 made from this fibre, which is said to be 

 very superior for many hygienic uses, as for 

 rheumatism and skin-diseases. Vests, draw- 

 ers, loose shirts, etc., are also made of this 

 material. In the process of manufacture an 

 ethereal oil is obtained, very useful as a sol- 

 vent, and as a curative agent. Gas is made 

 from the refuse, and used for lighting the 

 manufactories ; or the entire refuse may be- 



