VOL. XXXVII.] I'HILOSOPHICAL TRANSACTIONS. 515 



arise a very fine streain of water from the vertex of the cone, in the manner of 

 a fountain, from which there issued a fine steam, or vapour, whose particles 

 were so small as not to be seen; yet it is certain that it must be so, since the 

 under side of the tube was wet; and though there does not always arise that 

 cylinder of water, yet there is always a steam of invisible particles thrown on 

 the tube, and sometimes to that degree as to be visible on it. When some of 

 the larger cups are used, they are to he filled as high as may be, without run- 

 ning over; the surface will be flat about the middle part; but when the tube is 

 held over it, the middle part will be depressed into a concave, and the parts 

 towards the edge be raised ; and when the tube is held over against the side of 

 the water, the little conical protuberance of water issues out with its axis hori- 

 zontally, and after the crackling noise, returns to the rest of the water; and 

 sometimes there will be thrown out of it small particles of the same, as from 

 the smaller portions of water above-mentioned. 



The last experiment was repeated with hot water, when the water was at- 

 tracted much stronger, and at a much greater distance: the steam arising from 

 the vertex vvas in this case visible, and the tube was sprinkled with large drops 

 of water. Mr. G. tried the experiment in the same manner on quicksilver, 

 which was likewise raised up; but by reason of its gi-eat weight, not so high as 

 the water; the snapping noise was louder, and lasted much longer than in the 

 water. 



The Method of making the best Mortar at Madras in the East Indies. By Isaac 

 Pyke, Esq. Governor of St. Helena. N" 422, p. 231. 



Take 15 bushels of fresh pit-sand, well sifted: add to it 15 bushels of stone- 

 lime: let it be moistened or slacked with water in the common manner, and so 

 laid 2 or 3 days together. Then dissolve 2n lb. of jaggery, which is coarse 

 sugar, or thick molasses, in water, and sprinkling this liquor over the mortar, 

 beat it up together till all is well mixed and incorporated, and then let it lie by 

 in a heap. Then boil a peck of gram, (which is a sort of grain like a tare, 

 or between that and a pea,) to a jelly, and strain it otF through a coarse canvas, 

 preserving the liquor that comes from it. 



Take also a peck of myrabolans, and boil them likewise to a jelly, preserving 

 that water also as the other ; and if yon have a vessel large enough, you may 

 put these three waters together, that is, the jaggery water, the gram water, 

 and the myrabolan. The Indians usually put a small quantity of fine lime in it, 

 to keep their labourers from drinking it. 



The mortar beaten up, and when too dry, sprinkled with this liquor, proves 

 extraordinary good for laying brick or stone, keeping some of the liquor always 

 3u 2 



