50 PHILOSOPHICAL TRANSACTIONS. [aNNO l666. 



and last part of these observations contains another instance (in addition to those 

 mentioned in a former communication) of a white fluid, resembling milk, being 

 drawn from the vein of a patient who was ordered to be blooded. 



To preserve Ice and Sjiozv hy Chaff. By Mr. Wm. Ball. 



N' 8, p. 139. 



The snow and ice-houses at Leghorn in Italy are commonly built on the 

 side of a steep hill, being only a deep hole in the ground, by which means they 

 easily make a passage out from the bottom of it, to carry away all the water, 

 which, if it should remain stagnating there, would melt the ice and snow. 

 They are thatched with straw in the shape of a saucepan-cover, that the rain 

 may not enter them. This pit is filled full of snow or ice, which must be of 

 the purest water, to be used in their wine, after first spreading the bottom 

 very well with chafF; I think they use barley chafF. Then, as they put in the 

 ice or the snow, (which latter they ram down,) they line the sides very thick 

 with such chaiF, and afterwards cover it well over with the same. In half a 

 year's time it is found not to have lost above an eighth part of its first weight. 

 Whenever they take it out into the air, they wrap it in this chafF, and it thus 

 keeps exceeding well. 



The other usual way, both in Italy and other countries, to preserve snow and 

 ice, is with straw or reed ; as is particularly related by Mr. Boyle, in his Ex- 

 perimental History of Cold. 



Directions for Seamen bound for long Voyages. By Mr. Rooke. 



N' 8, p. 140. 



It being the design of the Royal Society, for the better attaining the end of 

 their institution, to study nature rather than books, and, from the observations 

 made of the phaenomena and efFects she presents, to compose such a history 

 as may lay a foundation for solid and useful philosophy : For this purpose they 

 gave orders to several of their members, and among others to Mr. Rooke,* 



* Mr. Lawrence Rooke, a distinguished astronomer and mathematician, was bom at Dept- 

 ford near Greenwich, in l623. He was educated at Eton school, whence he removed to King's 

 College, Cambridge, in 1639. But in the year 1650 he settled at Oxford to enjoy the company of 

 several eminently learned men residing there, where he associated witla those philosophers who after- 

 wards formed tlie Royal Society. In l652 Mr. Rooke was chosen professor of astronomy in Gres- 

 ham College, London, which appointment in 1 657 he exchanged for tlie geometry professorship. 

 Having enjoyed these situations some years before the restoration in l658, most of those gentlemen 

 who had been accustomed to assemble with him at Oxford, coming to London, joined with other 

 philosophical persons, and usually met at Gresham College to hear Mr. Rooke's lectures, and after the 



