374 
THE MEDITERRANEAN NATURALIST 
versal arbiter in all disputes between the mem- 
bers of the various chapters, and what is more 
strange the practice was not only sanctioned, but 
encouraged by the laws of the community. 
Long after duelling had been abolished, and 
declared illegal in European countries, it conti- 
nued to flourish under the fostering care of this 
belligerent brotherhood. 
But even among them the practice was subject 
to numerous restrictions, the infraction of any 
of which led to the incurment of most severe 
penalties. Of these one of the most curious was, 
that the principals were allowed to fight in one 
particular street only, and that even there, if 
ordered to put up swords by either a /might, a 
priest , or a woman they were bound to instantly 
obey. 
In so crowded a city as Valletta it might be 
thought that the difficulties thus placed in the 
way of duelling would be tantamount to its 
absolute prohibition: but this was not so. On the 
walls of this street are still to be seen numerous 
painted crosses indicating the places where duels 
had been fought, and knights had been slain. 
In a letter which Mr. F. Byrd one F. Pa. S. wrote 
to a friend of his just before the occupation of the 
islands by the English, he recounted a curious 
incident connected with the Maltese practice of 
duelling which occurred but a short time before 
his arrival and for the truth of the particulars of 
which he could therefore vouch. Two knights had 
hail a dispute at a billiard table and one of them 
aft er usin a great deal of abusive language, added 
a ow. To the astonishment of all Malta after so 
great a provocation he absolutely refused to fight 
Lis antaguni V The challenge was repeated and 
time vwii given to him to reflect on the conse- 
quence, i.iu he still refused to enter the lists. He 
v. a id on condemned by a court of justices to 
make t;m amende honorable in the church of St. 
John for m days successively; and to be confined 
in a dungeon without light for five years after 
which lie \v;n to remain in the castle of St. Elmo 
lor life. This sentence was rigorously carried 
out. 
Diamond Making 
The philosopher’s stone is not sought by the 
modern chemist, yet he aims to transform common 
materials into brilliant gems. As long ago as 1880, 
Mr. Hannay showed diamond-like crystals which 
had been formed on heating under great pressure 
in an iron tube, a mixture of lithium, lampblack, 
essence of paraffin and bone oil. The nitrogenous 
compounds of the last substance w T ere supposed to 
to have played an important part. M. Henri 
Moissan has noj obtained carbonado, or black, 
diamond, and even some minute crystals of the 
colourless gem, by a process in which carbon from 
sugar is dissolved in a mass of iron and allowed 
to crystallize out under high pressure. The pres- 
sure is produced by the expansion of iron during 
condensation. The carbon is strongly compressed 
in an iron cylinder closed with a screw stopper 
then a quantity of soft iron is melted in an electric 
furnace, and the cylinder is plunged into it. The 
crucible is at once taken from the furnace, splashed 
with water, and slowly cooled in air. The iron 
is dissolved away by repeated treatment with 
acids and other reagents. Researches on the 
solubility of carbon in iron, silver and their alloys 
are being continued, and it is hoped that diamonds 
of appreciable size may soon be produced. 
The Marls and Clays of the 
'Maltese Islands* 
BY, 
John H. Cooke, B.Sc., F.G.S. 
II. 
The pressure of the overlying strata upon the 
plastic Clays has caused the original thickness of 
the formation to be much diminished in many 
parts of both islands, but especially so in the 
smaller plateaux and in the isolated hills ; while 
in other localities the taluses that have been 
formed at the outcrops have, by cloaking the 
hillsides and cliff-sections, caused the thickness of 
the Clays to appear to be double and even treble 
of what it really is. It is to these estensive taluses 
that the many exagerated estimates of the thick- 
1 ness of the formation are due. 
