
APRIL 15, 1915] NATURE 193 
Miners’ lamp glasses. i Parts : Parts 
or (11) Sand “He ... 68-0 Potassium carbon- 
arts Parts 5 = 
.6) Sand sie = 05:0 Potassium nitrate 3-0 Alumina (Al,O,) 4°0 _ate  (K,CO,) 10-0 
Alumina (Al,O,) 1-0 Godinml carbonate Calcium carbon- | Sodium — carbon- 
Calcium carbonate 0-6 (Na,CO,) . 140 ate 12-8 | ate (Na,CO,) 26-0 
Arsenious oxide Boric anhydride These glasses do not lose their easy-working quali- 
(As,O5) : 20 (B.O,) +++ 24°0 | ties after repeated heating and blowing, and are plastic 
Antimony oxide over a long range of temperature. They require a 
(Sb,O,) s. «6«TO temperature of at least 1400-1500° C. for complete 
A colourless and fusible glass withstanding rapid 
changes of temperature exceptionally well. 
ss Parts Parts 
(7) Sand nt -.. 65:0 Potassium 
Alumina (Al,O,) 1-0 Tirenteie a) Ere) 13-0 
Calcium carbonate 0-6 Anhydrous borax 
\rsenious oxide (Na,B,O,) . 26:68 
(As.O,) Eo 2:0 Borie anhydride 
Antimony oxide (B,O,) Paes 
(Sb,O,) san gt) 
The same glass as (6), but the ingredients have 
been varied to avoid the use of so much _ boric 
anhydride, which is at present apparently difficult to 
obtain on a commercial scale. 

Resistance-glass. 
Parts Parts 
(8) Sand 30 aba (se = | Sodium carbonate 
Alumina (Al,O,) 2:5 | (Na.CO,) 10-2 
Magnesia (MgO) 5:0 Borax anhydrous 
Zinc oxide (ZnO) 8-0 (Na.B,O,) 13:0 
A glass almost identical in its general behaviour 
with Jena resistance glass; withstands changes of 
temperature well, but, like Jena, is not suitable for 
working before the blowpipe. It darkens and tends 
to devitrify; operations—such, for instance, as sealing 
side tubes into flasks—are difficult, if permanent and 
neat joints are required. 
Formula No. 3, recommended for pharmaceutical 
purposes, ampoules, etc., may be substituted for the 
resistance glass with advantage, as the ampoule glass 
lends itself very well to blowpipe work, and is also 
especially resistant chemically. 
Alternative for combustion tubing. 

incorporation of the ingredients in order to obtain that 
homogeneity which is necessary for resistance to rapid 
changes of temperature and ease of working before 
the blowpipe. 
No. (10), containing potassium nitrate, is considered 
the better of the two, and is more easily incorporated. 
The committee considers that the formulas obtained 
and the worlk done on the various glasses justify it 
in the opinion that there is now information available 
for the manufacture of all the important glasses used 
in the laboratory and for industrial purposes, which 
have hitherto been mainly obtained from abroad. 
UNIVERSITY AND EDUCATIONAL 
INTELLIGENCE. 
Lonpon.—Prof. T. G. Brodie, professor of physio- 
logy in the University of Toronto, will deliver a course 
of four lectures on ‘‘The Gases of the Blood”’ at 
King’s College, London, on May 31, June 2, 7, and 9. 
These lectures take the place of those previously 
announced; they are free to medical students, to 
internal students of the University, and to medical 
men on presentation of their cards. 

Mr. A. G R. Fourerton has been appointed lec- 
turer in public health at the London (Royal Free 
Hospital) School of Medicine for Women, in succes- 
sion to Prof. W. J. Simpson, resigned. 
Tue Education Committee of the County Council 
of the West Riding of Yorkshire has arranged a 
summer vacation course for teachers, which is to be 
held at Bingley Training College from August 4 to 18 
next. Four evening lectures will be given during the 
course, including one by Mr. Mackinder on how much 
geography and history can be taught within the limits 
of the elementary school. 
The general course makes 
Parts Parts 
(9) Sand nae s+ 72:0 Potassium nitrate 
Alumina (AlI,O,) 10.0 (KNO,) 3:0 
Calcium carbon- Sodium — carbon- 
ate Ee 11-0 ate (Na,CO,) ... 11-2 
Magnesia (MgO) O-5 
Borax anhydrous 
(Na,B,O,) ... 7-2 
This glass is capable of withstanding high tempera- 
tures and rapid changes of temperature; works well 
before the blowpipe, and is free from the chief defect 
of Jena glass—namely, the readiness with which it 
becomes cloudy, and finally quite opaque after pro- 
longed use. 
By slight modifications of this formula, almost any 
degree of hardness can be obtained. ’ 
In formulas (8) and (9) substances such’ as magnesia 
(MgO) and zinc oxide (ZnO) can be added in the form 
of carbonates if the actual percentages of MgO and 
ZnO respectively present in the carbonates are known. 
Soft soda-glasses suitable for tubing and for X-ray 
bulbs. 
t Parts Parts 
(10) Sand... ... 68-0 Potassium nitrate 
Alumina (Al,O;) 4:0 (KNO,) - 1455 
Calcium carbon- Sodium carbonate 
ate (CaCO,) 128 (Na,CO,)  ... 26-0 
NOW 2372, VOL Osi 

provision among numerous other subjects for lectures 
on the teaching of informal domestic work in schools, 
and the special courses include lectures on animal and 
plant life. The primary object of the courses is to 
increase the educational spirit and efficiency of persons 
teaching in the West Riding, and to enable them to 
supplemeat their knowledge of the various subjects, 
and of the most approved methods of teaching them. 
All particulars of the course, including time-tables, are 
given in the “Bingley Vacation Course Syllabus,” 
copies of which may be obtained on application to the 
Education Department, County Hall, Wakefield. 
On March 6, Lord Hardinge, Viceroy of India, 
presided over the annual convocation of Calcutta Uni- 
versity, and delivered an address in his capacity of 
Chancellor of the University. The address is printed 
in the issue of the Pioneer Mail for March 12. The 
Chancellor referred to the increased interest which 
has arisen in Indian universities in the teaching of 
science subjects. University inspection combined 
with an ordered procedure in affiliation has consider- 
ably raised the standard of instruction in the colleges. 
Some of the laboratories attached to these institutions 
can now compare favourably with any in the world. 
The teaching staffs have been strengthened. The 
