$16 Scieiitific IntelUgenee. [April, 



it, and after it is sufficiently warmed tlie end of the little tube is 

 to be inserted where the lancet had made the puncture, and the 

 virus will immediately l)e taken up, so as to fill the bulb. The end 

 of the tube is now to be hermetically sealed by means of a common 

 blow-pipe at the flnme of the candle, which is a very simple 

 process ; and thus the vi: us may be preserved for any length of 

 time, and sent to any distance. If for immediate use, the tube 

 need not b^- sealed, but may be secured in any convenient mapner. 

 Any requisite number of these halls may be employed, and it is 

 proper to remark that the virus is never heated much above blood 

 heat. I need add nothing in praise of the invention : it speaks 

 sufficiently for itself, and has been used here for several years." 



XII. Insect on yip pie-Trees. 



I insert the following query at the request of a Correspondent :— 



*' There is an insect, a species of mealy glutinous creature, which 

 eats the bark of apple-trees so much iliat it destroys the tree. 

 Washing with lime does not eradicate it. What else might be 

 jubstituted effectually to kill it? " 



XIII. Mineralogy in Spain. 



The following extract of a letter from a scientific friend, who is 

 Kell acquainted with mineralogy and geognosy, will, I am per- 

 suaded, gratify every mineralogical reader : — 



" 1 h;ive gleaned very considerable information in the course of 

 my travels throuch Spain, although the present state of the country 

 is very unfavouralile to scientific research. The interior of the 

 peninsula is over-run by hordes of guerillas, who now rob and 

 murder all that they encounter. A careful examination of the 

 country is thus out of the question ; but 1 have availed myself of 

 every means within my reach ; the results of which I hope to be 

 enabled to transmit to you, and my other scientific fiicnds, in the 

 course of a few months. I feel very much the want of a portable 

 harorneter, as I have had some good oiiportunities of ascertaining 

 several heights. The plains of Castile are highly elevated, I appre- 

 hend, exceeding considerably 1000 feet. I judge from the differ- 

 ence between their height and that of the Mountains of Santander, 

 contrasted with the apparent elevation of the latter above the sea. 

 The thermometer fell oply about 5" on gaining the highest points 

 of that range from the plains of Castile; hut it rose upwards of 16* 

 on descending to the sea shore on which the town of Santander 

 stands. I shall certainly visit Cadiz, and examine the quicksilver 

 mine, as well as that of Gadalcanal. I have not yet found either 

 andalorezite or arragonitc. Near Santander I found in a cavity of 

 the common limestone a considerable imbedded mass of yellow 

 amber. Although within sea water mark, it was so firmly connected 

 with the rock tltat I am induced to believe that it has been exjwsed 



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