69 



should be perfectly new. If fluids are used to clean the bottle, 

 such should consist only of mineral acids which must be fastidi- 

 ously rinsed out afterwards. 



People sometimes think that, given half a pint of water, a 

 few tricks can be performed and the figures of a complele analysis 

 obtained. The substance sought for in the analysis are present 

 in such minute quantities that this volume of water can only 

 serve for determining the hardness, and for anything like a 

 moderately complete analysis, nothing less than a litre suffices; 

 moreover, even this is inconveniently small and a " Winchester 

 quart" (half an imperial gallon) should be regarded as the most 

 suitable quantity. In searching for some salts for certain pur- 

 poses as much as three Winchesters may be necessary. 



In filling the bottle no intermediate vessel should be used. 

 The water should be allowed to flow from the tap straight into 

 the bottle taking care that it does not wash one's hand on the 

 way. If being taken from a tank, a river, or some similar source, 

 the bottle should be plunged below the surface and the stopper 

 removed now and not before so as to prevent any scum entering. 

 Before actually taking the sample, the bottle should be rinsed 

 several times with the water, and filled to overflowing at least 

 once during the operation so as to drive out any possible vapours 

 which are able to survive many ordinary rinsings. Further, some 

 thought should be given to the act of emptying the bottle after 

 each rinsing, for as water goes out air e-oes in, and therefore to 

 hold the inverted bottle close over a foul sink, for example, would 

 be very objectionable. The bottle being filled to within an inch 

 of the stopper, a clean piece of linen should be immediately tied 

 t : ghth- over the latter and the sample stored for as little time as 

 possible before analysis. 



In collecting a sample for bacteriological examination it is 

 necessary to take certain other precautions in addit : on to the 

 foregoing, such as sterilising the tap, etc. 



The fullest possible particulars of the water and its source 

 should always accompany a sample. 



REMINISCENCES OF EGYPTIAN EXPLORATION. 



Report of a lecture by 



Field -Mar shall LORD GRENFELL, g.c.b., g.c m.g., ll.d., f.s.a. 



(Given before the Archaeological Section, March 9, 1918.) 



On Saturday, March 9, 1918, Field-Marshal Lord Gren- 

 fell, F.S.A., gave an address to a crowded audience in the 

 Society's Room, entitled "Reminiscences of Egyptian Explora- 

 t : on. ' He went back to the time when Egypt was threatened 

 with an invasion from the trocps of the Mahdi, and a large force 



