144 
DR. P. P. FRANKLAND ON THE QUANTITATIVE ESTIMATION OF 
V. Roof of Science Schools. October 19, 1886. Wind S.E., gentle, constant in 
direction. Rain during morning, roads wet, roof and pavement nearly dry. 
4.58 p.m. to 5.32 p.m. 
Nos. 1 and 2. Flask method .—(Double plugs.) 
No. 3. Hesse’s method. 
Nos. 1 and 2 alternated in aspiration. No. 3 aspirated simultaneously in 
close proximity, and with the tubes inclined at the same angle. 
No. 1. Flask method. 
Volume of air — 18 litres. 
Construction of plugs. —(a) Glass-wool only. 
(5) Sugared glass-wool and sugar-powder. 
Rate. —8 strokes per minute. (Tube exposed 9 minutes.) 
r . 7 . n 7 / \ f 42 moulds. 
Colonies in flasks. —(a) 53 j ^ ^ 
(h) 0. 
No. 2. Flask method. 
Volume of air =18 litres. 
Construction of plugs. —(a) Sugared glass-wool. 
( b) Sugared glass-wool and sugar-powder. 
Rate. —5 strokes per minute. (Tube exposed 13 minutes.) 
Colonies in flasks.—(a) 5g| 2 ^ “ oulds> 
. {h) °‘ iq ' 
Control-tube, containing plug of sugared glass-wool, exposed 36 minutes :— 
Colonies in flask, 0. 
„ 7 . . 7777 .[No. 1 (glass-wool), 27 colonies. 
I) Litres of air yielded, therefore, in \ ^ 
J J J * [No. 2 (sugar-wool), 28 
No. 3. Hesse’s method. 
Volume of air = 9 litres. 
_ 7 . . 7 r 16 moulds. 
Colonies in tube . . . 314 
1 0 hq. 
,, control-tube . 2* moulds. 
VI. Roof of Science Schools. October 20, 1886. Wind W. by S.W., gentle, but 
increasing during experiment; roads wet, pavement dry. Rain during previous 
night. 12°'8 C. 
Nos. 1 and 2. Flask method .—(Double plugs.) 
No. 3. Hesse’s method. 
Nos. 1 and 2 alternated in aspiration; No. 3 aspirated simultaneously in 
close proximity, the tubes being inclined at the same angle. 
* This tube was somewhat overgrown by a liquefying colony, so that this result is probably too low. 
