1875.] Human Levitation. 31 
for a single article has prevented any detailed account of 
the various methods of intercommunication in trains, which, 
by the Regulation of Railways Act of 1868, is directed to 
be provided in every train carrying passengers and travelling 
more than twenty miles without stopping, or of the several 
other minor arrangements suggested, or introduced, with 
the view of more effectually securing the safety of pas- 
sengers. 
With the adoption of the improved methods of interlock- 
ing signals and points, and of the block system, no doubt 
very considerable addition is made to the safety of travellers, 
but the companies are thereby put to great additional 
expense, both in first cost and for subsequent maintenance, 
for which the only return they can look to is an increased 
immunity from accidents. To ensure absolute security is 
not, however, possible, by the adoption of any means hitherto 
suggested. The introduction of the block system necessi- 
tates the maintenance of a considerably increased staff of 
signallers, and at the same time it introduces so many 
additional elements of human fallibility, whose’ liability to 
err can only to a limited extent be guarded against by the 
employment only of competent men, and the strict enforce- 
ment of such rules and regulations as it may, in each case, 
be considered advisable to frame for their guidance. 
Ill. HUMAN LEVITATION ; 
ILLUSTRATING CERTAIN HISTORICAL MIRACLES. 
CCORDING tto Archbishop Trench, a physical defi- 
nition of man might be given as “the animal that 
weighs less when alive and awake than dead or 
asleep ” (“‘ Notes on the Miracles,” ed. vii., p. 289). This 
he calls ‘‘ a faét which every nurse who has carried a child 
would be able to attest; and refers to Pliny (‘‘ Natural 
History,” vii., 18). He concludes, “‘that the human con- 
sciousness, aS an inner centre, works as an opposing force 
to the attraction of the earth, and the centripetal force of 
gravity, however unable now [t.e., since Adam’s fall] to 
overbear it.” Unluckily, Pliny’s words do not make this 
form of psychic force a human prerogative. They are, 
‘‘Mares prestare pondere; et defuncta viventibus corpora 
omnium animantium, et dormientia vigilantibus.”” Perhaps, 
even in the absence of any accurate experiments, we might 
