G. H. F. Nuttall 
487 
Abyssinians and Gallas, and if they cannot procure it they shave their 
heads. Girard (1885, p. 1083) is no doubt correct in attributing the 
effect of oils and grease on the louse to their asphyxiating the insects 
by occluding the respiratory apparatus, and some recent authors 
appear to have reached the same conclusion. Moniez (1889, p. 227) 
recommends simple olive oil for the destruction of Ph. pubis, adding, 
however, that it does not destroy the nits. Heymann (18. vm. 1915, 
p. 311), writing of the unfavourable influence of naphthaline-vaseline 
on body-lice, thought that the effect might be due solely to the vaseline 
and that any grease might exert a similar influence, adding that an old 
treatment for lice on pigs consists in the application of tallow. Weidenheld 
and Puley (1915, p. 153), moreover, record that Carpathian shepherds 
keep off body-lice by soaking their clothes in melted butter; they wear 
such clothes for months unwashed. These authors conclude that the 
lice either do not lay eggs on greasy surfaces or object to the rancid 
odour 1 . Hase (xi. 1915, p. 158), whom I have cited on p. 92, states that 
many soldiers told him that dirty greasy shirts were a safeguard against 
lice and that some of the men temporarily relieved themselves from 
the attacks of lice by greasing their bodies. 
There are no recorded experiments upon the destruction of lice by 
oils and fats that possess any value. Ivinloch (1915, pp. 1038-1041) 
states that vaseline has “no effect” and that colza oil has “little effect,” 
whilst Castellani and Jackson (1915, pp. 253-255) assert the contrary, 
namely, that vaseline kills “at once.” In neither case do the authors 
mention how they made their experiments and in neither case are the 
statements credible. Lelean (1917, p. 161), who recommends greasing 
the seams of clothing to kill lice and nits “at once” by asphyxiation, 
also gives no evidence to prove that lice are killed and not merely 
temporarily immobilized by the grease. 
In the absence of direct experiments, the practical experience 
summarized in the paragraph preceding the last gives grounds for 
reflection. It appears reasonable to suppose that oil or grease of any 
kind possessing a sufficiently low melting point will with time suffice 
to asphyxiate lice and their nits with which they are brought in contact 
without the addition of medicaments. This would point to the fatuity 
of complex recipes for ointments of the kind elaborated by medical 
men and others but for one reservation, namely the addition of (a) 
medicaments having antiseptic, curative or soothing properties which 
1 Frankel (1915, p. 313) adds that butyric acid (vapour?) is fatal to lice in an hour 
and a quarter. 
