40 0 REPORT—1863. 
On Disinfectants. By H. B. Conny, F.C.S. 
It was remarked by the author, that the idea of artificial disinfection by chemical 
means was not opposed to the operations of nature, since the action of the air in 
overcoming the foulness which is inseparable from the congregating together of 
men in dwellings is explainable only by the laws of chemistry. The atmosphere 
is an admixture of chemical substances, whose influence on organized being, whe- 
ther in its constructive or destructive effects, is of a truly chemical nature. In 
studying, consequently, the best means of ‘seconding nature in her efforts for dis- 
posing of the waste products of organic life, we had only to copy her admirable 
processes, in order to arrive at the most perfect results. The researches of recent 
times on the composition and economy of the atmosphere pointed clearly to oxygen, 
and especially to active oxygen, as the chief means by which natural disinfection 
is accomplished, There are two classes of circumstances in which the auxiliary aid 
of disinfectants is very frequently required to overcome unwholesome influences, viz., 
1st, against the deleterious emanations which generally proceed from the bodies of 
men, especially when labouring under disease, and more particularly when such 
disease is of a contagious nature; 2nd, against the taint of organic decomposition. 
In both these cases the chemical objects to be kept in view were substantially the 
same. The infective material in either case is supposed to be an organic com- 
pound, declining by successive transformations from a highly complex form towards 
that state of ultimate repose which belongs to complete oxidation. Its dangerous 
qualities are dependent on its condition while passing through those steps of 
transition during which it acts after the manner of a ferment. Disinfectants are 
of two classes :—I1st, those which, by fixing the organic matter in a form unfayour- 
able to oxidation, thus reduce to the utmost its tendency to undergo chemical 
‘change, and which are more properly designated antiseptics; 2nd, those which 
more or less rapidly break up the organic matter by producing its oxidation and 
conversion into imputrefiable products, and which alone are properly designated 
true disinfectants. The advantages possessed by the preparations indicated by the 
author were thus summed up:—they had no smell whatever of their own, gave 
off no odorous gas during their operation, and when diluted for use were devoid of 
perceptible action, except on offensive matter; they were thoroughly efficient and 
poe in their effects, disinfecting as well as deodorizing ; perfectly safe to us, 
“because not poisonous; not mistakeable for other substances, on account of their 
characteristic colours ; capable of being regulated as to quantities required by the 
‘depth of colour of their solutions; and applicable in a great number of cases for 
which no other disinfecting agents can be employed. 
On Fire-clay Goods*. By Josepn Cowen, Jun. 
The author stated that fire-clay, which is obtained in large quantities in the two 
counties of Durham and Northumberland, usually lies beneath the coal-measures, 
in layers varying in thickness from 12 inches to 5 or 6 feet. The refracto 
-character of any sample of fire-clay is determined by the proportions in whic 
silica and alumina are present, and by the absence of lime, iron, and other easily 
fluxible substances. The best descriptions of tire-clay—those which, when manu- 
ip 2. 3. 4. 5. 6. 7. 
Silica...... ie He 51-10} 47:55| 48-55] 51-11 | 71:28 | 83:29 | 69-25 
ot Adhuvnlina® .uia. Pd) 31:35 | 29:50] 30-25] 30-40 | 17-75 | 810 | 17-90 
Oxide of iron ...... 463} 913| 4:06] 4911] 9.4, 188, | 297 
Lined Io .alneyie te. 1:46| 1:34] 1:66] 1:76 ( 130 
Magnesia .......... 154] 0-71} 191] trace | 230) | 2-99 
Water and organic 
MALE ORS ache Teh 10-47 | 12-01] 10°67) 12:29 | 694 | 364 | 7-58 
aS ree ee) a de eo bee ee sennd eet nels Sale), | 
* This paper was drawn up by the author at the request of the Local Committee. 
