5 $ 
SEA SAND. 
slightly magnetic, but becomes strongly so after being heated ; 
while Pyrites is only magnetic after ignition, when it loses 
sulphur and becomes converted into Pyrrhotine. Magnetite 
certainly occurs in the basalt of the North of England. 
The word attractable has been used because a piece of iron 
may be attracted by a magnet without being itself a magnet. 
A good test for a magnet is to find whether it can repel as well 
as attract another magnet, and a compass needle makes a 
convenient test magnet. Now at first the shining hlack 
particles do not appear to have this power of repulsion. But 
if a small glass tube full of them is held in the neighbourhood 
of a strong magnet, and there gently shaken, the tube full of 
particles will then behave as a magnet attracting one end of a 
compass and repelling the other. I argue then that the 
particles have really been magnetic all the time, though this is 
not evident so long as they are arranged anyhow ; but that the 
gentle shaking in the neighbourhood of a strong magnet allows 
them to arrange themselves all in the same way, and that 
after this arrangement has taken place their united effect is 
appreciable. 
The existence of any large mass of magnetic material along 
a coast line may have a disturbing effect on ships’ compasses. 
After a recent shipwreck there were two stories—the captain's 
which alleged that his compasses were at fault, and another 
which pointed to errors of observation or judgment due to 
Alcohol. The supposed causes, do not exclude each other, but 
their coincidence may well be fatal to safe navigation. I 
have no evidence, however, that any such magnetic perturba¬ 
tion occurs off the Scarboro' coast. 
Nor are these magnetic particles the only iron in the sand. 
Many yellow sands when boiled with acid lose some of their 
colour and turn whiter. The yellow substance passes into 
solution, and this solution may be examined for iron in another 
way. The test is one of great celebrity. It has been the 
means of reviving the writing in some of the most ancient 
Biblical manuscripts. For instance, when Rendall Harris 
went from Cambridge to explore the library in the monastery 
on Mount Sinai, he knew that the monks would not approve 
of his borrowing their manuscripts. Therefore he took 
