SCIENTIFIC SUMMARY. 
321 
phorus to pass into the condition of phosphoric acid; which is precipitated 
in the state of a magnesian compound. Several causes of error exist in 
this treatment, for — 1. A part of the phosphorus escapes the action of the 
agents, and disengages itself in the form of an hydrogenous compound. 
2. It is necessary to act upon very diluted solutions to prevent the ammo- 
niacal-magnesian phosphate mixing with the oxide of iron, in which case it 
is difficult to collect the small amount of phosphate deposited on the sides 
of the vessel in which the precipitate is made. 3. The arsenic which may 
he contained in the iron enters into the magnesian precipitate in the form of 
arseniate as insoluble as the phosphate. 
Creosote oil as a Source of Heat . — We have it on the authority of our 
contemporary, the Journal of the Society of Arts, that Mr. W. D. Dorsett 
has brought out a system by which not the creosote oil but its distilled 
vapour, which is more powerful, is made to do the work of coal in heating 
iron plates to the heat necessary for bending them for ships’ armour-plating 
and other similar purposes, where the advantages sought are a very high 
and at the same, time so equal a temperature as that, while producing the 
required amount of ductility in the material to be operated upon, it shall 
not be deteriorated in its fibrous tenacity. For some two or three months 
Mr. Dorsett has been experimenting with his patent fuel in Woolwich 
Dockyard, and so satisfactorily to the Admiralty authorities, that they have 
instituted tests at Chatham, with a view to the preparation of the armour- 
plating of the Sultan armour-plated ship now building in that dockyard. 
The advantages may thus be shortly summed up as compared with coal : — 
A greatly diminished cost and saving of time in producing the required 
heat of iron, as well as a saving of labour ,* an absence of refuse, and a 
surface altogether free from scale. As regards the effect of this new mode 
of heating upon the metal itself, one of the dockyard operatives declared, 
somewhat emphatically, that the commonest iron treated by it came out of 
the furnace as good as the best Low Moor. The apparatus is simple, and 
inexpensively applicable to existing coal-furnaces. It consists of a reservoir, 
from which the oil is pumped up as wanted into a receiver, where, by the 
application of heat, the vapour is generated, and this is passed through pipes 
into the furnace, and used as fuel in the ordinary way. 
MICEOSCOPY. 
The Microscopical Work of the Quarter . — The existence of the Monthly 
Microscopical Journal so stimulates histological inquiry that the brief space 
we are enabled to give to the subject does not admit of a thorough record. 
For the benefit of those who can specially devote their attention to this 
subject, we give the titles of the papers which have appeared in the last 
three numbers of the Monthly Microscopical Journal : — 
April . — Notes on the Scale-bearing Podurce. By S. J. Mclntyi’e, 
F.E.M.S. — On the Fibres of the Crystalline Lens of Petromyzonini. 
With a Note on the .^Esophagus of the Aye-Aye. By George Gul- 
liver, F.E.S. — Two New Forms of Selenite Stages. By Frederick 
Y 2 
