Aug. 17, 1871] 
NATURE 
313 

with a little care it was not difficult to adjust the level of 
the paper, so that very little displacement was called for 
to meet the requirements of the pen’s descent towards the 
centre of the figure, and that little was granted at once 
by the facility with which the india-rubber yielded to the 
demand. When the suspension was ill-adjusted, so that 
the pen-point pressed too heavily on the paper, there was 
a slight lateral displacement ; but this danger was reduced 
almost to #z/ by using at each corner two elastic bands 
at right angles, instead of only one, ensuring resistance 
‘to any rotatory jerk in either direction, 
A little more practice in the manufacture of the glass 
pen enabled me to improve the delicacy and uniformity of 
the lines. The chief difficulty lay in breaking the capillary 
tube square to the axis. The tube delighted in oblique 
fracture, which gave an oblique pore when the edges were 
smoothed in the flame, and the oblique pore was apt to 
write unequally in different directions, often refusing to 
write at all on one side of the figure, when the pore was 
not facing its work. Only now and then was the first 
fracture fortunately square ; generally I had to pick at it 
with the finger-nail to reduce its obliquity. Latterly, I tried 
to ensure success by coating the point with a thin layer of 
bees’ wax, tracing a fine groove in the wax round the 
slender tube, and allowing a drop of solution of fluoric 
acid to adhere round the groove until the acid had eaten 
into the glass and made it ready to break at the ring of 
corrosion. Then the remainder of the wax was washed 
off with turpentine, and the point was ready for its ‘ bap- 
tism of fire.” In this way I succeeded well with one or 
two pens, but the process was rather troublesome. That 
“baptism of fire” was another dangerous crisis in the 
early life of the pen, for the risk was great that it might be 
exposed to the flame just a fraction of a second too long, 
sealing the liquid lips for ever. A good way of testing the 
size of the pore—it was much too small to be examined by 
the naked eye—was to blow through it and notice the size 
of the current of air disturbing the pale blue flame of the 
Bunsen’s burner. Alternately dipping the point for the 
tenth of a second in the outskirts of the furnace, and 
quickly withdrawing it, and trying its calibre by the 
breath, it was seen that the air-current grew smaller and 
smaller after every dip in the flame, till I dared not dip 
again, and then I had recourse to a powerful pocket-lens 
to examine the size of the pore and the smoothness of its 
lip. The diameter of pore of the best pen I have suc- 
ceeded in making is 1-500th of an inch. 
I grew discontented with common black ink for my 
pendulum-curves ; it was apt to coagulate and choke the 
pore, frequently requiring the solvent power of sulphuric 
acid to restore free passage. Besides, I wished to have 
several figures superposed on the same paper, yet so that 
each should remain distinct. So I procured a set of 
coloured inks at the stationer’s, price 1d. per bottle, and 
with these I was able to give additional interest to the 
sheets that were rapidly accumulating from all these trials 
of new ink, new pens, and new pendulums. For I soon 
grew discontented also with my first pendulum ; its tripod 
was not strong enough, and its cord-hinges were very weak, 
and were fast fraying under the strain of 5olbs. of lead in 
habitual oscillation below, and I feared a snap and a crash. 
I kept it in my bedroom, and at midnight I heard it creak, 
and could not rest until I had insinuated a rush-bottomed 
chair between the legs of the tripod, immediately below 
the lead, to break the fall which I fully expected. How- 
ever, nothing happened, and in the morning I changed 
the frayed string for a trustworthy cord, and slept se- 
curely next night. I also made a new tripod with the aid 
of three surveying-poles, and improved the attachment of 
the pen by making it slide in a hole bored in the end 
of the rod, with a lateral screw to fix it at any required 
height. 
HUBERT AIRY 
(To be continued.) 



THE BRITISH ASSOCIATION MEETING AT 
EDINBURGA 
EDINBURGH, Friday morning 
HE work—and play— of the Edinburgh meeting of 
the British Association is now over; the visitors 
have all left, except such as have remained to do honour 
to the memory of the great Magician of the North ; in- 
deed, for the last two days the Southerners have dividea 
their allegiance between the British Association and the 
Scott Centenary. Instead of Spontaneous Generation and 
the Germ Theory of Disease, the Solar Eclipse and the 
great Dredging Expedition, we have heard quite as much 
of Abbotsford and Dryburgh, Jock o’ Hazeldean and the 
Laird of Dumbiedikes. 
As announced in our letter of last week, the concluding 
meeting of the General Committee was held in the 
University on Wednesday at one o’clock, Sir William 
Thomson in the chair, Dr. Hirst read certain regulations 
which were proposed by the Committee on Recommenda- 
tions to be adopted relative to the proceedings of the 
sections. They had reference to the organisation and 
constitution of the Sectional Committees, but were merely 
in regard to matters of detail. In an appended circular, 
authors of papers w ere reminded that, under an arrange- 
ment dating from 1871, the acceptance of memoirs, and 
the days on which they were to be read, were now as far 
as possible determined by organising committees for the 
several sections before the beginning of the meeting, It 
had therefore become necessary that an author should pre- 
pare an abstract of his memoir, of a length suitable for 
insertion in the published transactions of the Association, 
and that he should send it, together with the original 
memoir, to the general secretaries in London a certain 
time before the meeting. If it should be inconvenient to 
the author that his paper should be read on any particular 
day, he was requested to send information thereof to the 
secretaries in a separate note. These resolutions, after 
some discussion, were adopted, ‘The next subject referred 
to the General Committee on Recommendations had re- 
ference to Dr. King’s proposal that there should be a sub- 
section of Anthropology. Before the consideration of 
that suggestion was concluded, another came from 
Section D of a more definite nature ; and, on considering 
both propositions together, the Committee on Recommen- 
dations decided that they could not recommend the adop- 
tion of Dr. King’s motion, but that they could strongly re- 
commend the adoption of the other. They therefore recom- 
mended—“ That in future the division of the Section of 
Biology into the three departments of Anatomy and Phy- 
siology, Anthropology, and Zoology and Botany should be 
recognised in the programme of the Association meetings; 
and that the president, two vice-presidents, and at least 
three secretaries shall be appointed ; and that the vice- 
presidents and secretaries, who shall take charge of the 
organisation of the several departments, should be de- 
signated respectively before the publication of each pro- 
gramme.” That would virtually amount to the direct 
recognition of the three departments of Section D. 
Logically, it would be impossible to take any of these 
departments from Biology to make a separate section of 
it ; but they were recognised distinctly, and the gentlemen 
who would preside over these departments would be stated 
by name. The recommendation was agreed to. 
The following recommendations were then read and 
unanimously adopted :— 
“ That the President and Council of the British Asso- 
ciation be authorised to co-operate with the President and 
Council of the Royal Society, in whatever manner may 
seem to them to be best, for the promotion of the circum- 
| navigation expedition specially fitted out for carrying the 
physical and biological Exploration of the Deep-sea into 
| all the great oceanic centres. ; 
“That the President and general officers, with power to 

