Jor Microscopical and other purposes. 125 
surface of the wick. Excellent wicks may be made with 
concentric cylinders of thin mica, or of platinum foil. 
Fig. 5. Is another form of the lamp, without a wick, in which 
the diluted alcohol is burned in a flat platinum or metallic 
dish MN, which may be made to have a slight spontaneous 
oscillatory motion, for the purpose of bringing the fluid 
over the heated projections of the platinum. A common 
spirit-lamp OP, inclosed in a case, is placed below the pla- 
tinum dish MN, in order to produce sufficient heat for 
throwing ofl‘ the vapour from the diluted alcohol. 
A chimney, or a cylinder, of pale yellow glass may be 
placed round the flame, if it should be thought of any con- 
sequence to absorb the small portion of blue light which 
accompanies the yellow flame. 
Aut. XIX. — Biographical Notice of Mary Noble of Penrith, 
Cumberland, who is (1823) in the MTlth Year (flier Age, with 
some Remai'ks on Longevity By Thomas Barnes, M. D. 
^(Tary Noele, the subject of the following brief Memoir, w^as 
born at Haresheugh, in the parish of Kirkoswald, Cumberland. 
Her parents were poor labouring people, of the name of Salkeld, 
and were chiefly employed in agriculture. Both of them lived 
to be very old, and had ten children ; several of whom, also, 
reached a very advanced age. A copy of the register of her , 
baptism was lately shewn to me by Jonathan Nicholson of 
Penrith, with whom she now resides. Her baptism is dated 
September 17. 1716 ; and as children, at that time, were sel- 
dom baptised immediately after their birth, it is probable slie 
was born two or three months before. She was brought up 
with plain and simple food; and was accustomed, from her 
youth, to industry and hard labour. At thirty years of age 
she married to William Noble, a miller, by whom she had 
three children; all of whcm died of acute diseases, in their 
infancy. Mary Noble is a very short and small woman; and, 
at present, would not weigh more than between four and five 
* Read before the Wernerian Natural History Society, 31st May 1833. 
