392 
justifies the use of boric acid and borax as food preservatives. TTiley, 
Bigelow, and others (38), as the result of their study of the effect of 
boric acid and borax on man, have found that while the persons under 
exiDeriment were in many instances made temporarily ill by the quan- 
tities of boric acid administered, at the end of the year, after the final 
after j^eriod, they appeared to be, and so expressed themselves, in 
better j)hysical condition than when they entered on the experi- 
mental work. 
It has already been pointed out that salicylic acid and benzoic acid 
are only rarely used as milk preservatives. This is fortimate, since 
both of these substances must be looked upon as toxic, to a degree at 
least, and the former, at least, seems to be more or less cumulative 
in its toxic effects upon the system. The injurious eff'ects resulting 
from continuous small daily doses of salicylic acid were first pointed 
out by Brouardel (39), who made a plea for its discontinuance as a 
food preservative and for more thorough and systematic examina- 
tions of preserved foodstuffs by chemists and health officers. The 
effect of salicylic acid and the salicylates on man has also been investi- 
gated quite recently by Doctor IViley (10) and his coworkers at the 
hygienic table. He points out in his general conclusions that there 
has been a general consensus of opinion among scientists and medical 
authorities that salicylic acid and its compounds are very harmful 
substances and that the prejudice against them is perhaps greater 
than against any other form of food preservatives. I^Tiile he is still 
inclined to look upon it as a harmful substance, it is probably of less 
virulence than has heretofore been supposed. 
Attention has already been called to the use of hydrogen peroxide 
in the sterilization of milk. In its 3 per cent solution this substance 
has been employed by Budde (16) to sterilize milk at somewhat lower 
temperatures than those employed in the ordinary processes of pas- 
teurization, and attempts have also been made to remove all traces of 
the peroxide remaining in the milk after such treatment. According 
to Lakin (II), however, these attempts have not proven practicable, 
and this author therefore objects to Budde's process of sterilizing 
milk on the ground that it still contains small amounts of the un- 
changed hydrogen peroxide, and also in consequence of the injurious 
impurities which commercial solutions of _^liydrogen peroxide are 
liable to contain — such as boric acid and arsenic — which are present 
in the substances from which the solutions of hydrogen peroxide are 
made. He adds, however, that the consumption of milk sterijized 
by this method is not known to have jDroduced any injurious effects. 
P. Gordan (12) has shown that the small amounts of hydrogen 
j3eroxide employed by Budde in his process of sterilizing milk have 
practically no sterilizing action, and that if employed in quantities 
sufficient to sterilize, it imparts a taste to the milk and renders it 
