112 .ON BITTER CASSAVA. 



to dryness, and heated till it gave off no more water, and then weighed 

 again. 



It is, of. course, impossible to obtain the whole of the starch by grating 

 the root : I have, therefore, paid some attention to the time which the 

 pulp is allowed to remain undisturbed, before the starch is washed out 

 of it. No. III. was pressed and washed six hours after grating, so that 

 little time for the maceration of the cell-walls was allowed, and it only 

 yielded 23'57 per cent, of starch. No. II. was allowed to macerate during 

 two days, and yielded 32 - 9 per cent, of starch, including, however, the 

 small quantity contained in the tunica, which could not amount to much, 

 as the tunica altogether forms but three and a half to four per cent, 

 of the root. No. I. was allowed to macerate one day, and it yielded 28'44 

 per cent, of starch, not including that contained in its tunica. This 

 amount of starch is almost exactly the arithmetic mean between the per- 

 centage of No. II. and No. III., which is = 28 '24 ; thus corroborating my 

 surmise, that prolonged maceration, by weakening the cell-walls, will give 

 a larger yield of starch. The quality of the starch, however, suffers some- 

 what by prolonged maceration, — an accident which no doubt can be pre- 

 vented. The tunica and fibre have been kept back, in order to determine 

 the starch remaining in them. 



During the process of my experiments on cassava, I had occasion to get 

 acquainted with the very remarkable antiseptic power of its juice when 

 undiluted with water. 



Being desirous to see what structural changes the cassava would undergo 

 in contact with fermenting urine, in connection with the subject of 

 potato-disease, I mixed one volume of the pulp of cassava with three 

 volumes of recent urine, and allowed the whole to remain in a warm room, 

 in a vessel covered with paper. The whole mass dried up, without the 

 urine undergoing fermentation ; which is decidedly a great test of the 

 antiseptic qualities of cassava-pulp, and should cause it to be more fre- 

 quently employed in Surgery, as an antiseptic. — ('West India Quarterly.') 



THE STEEL SEA-BEACH OF TABANAKI, NEW ZEALAND. 



An instance, as remarkable as any which could be named, of the 

 discovery of the true character of some useful product of nature, after it 

 had lain long unknown and unemployed by man, though close beneath 

 his hand, has recently occurred in the district of Taranaki (New Plymouth), 

 New Zealand. For about seventeen miles along the coast of this 

 province, there is nothing to be seen but a dull, smooth beach, of a dreary 

 black hue, which is deepened by contrast with the snowy foam. The 

 beach is half a mile wide at low water, and its constituent particles or 

 grains have a slight metallic lustre, and are so small as to resemble fine 



