i 
Cfte popular Science iSttos 
AND 
BOSTON JOURNAL OF CHEMISTRY. 
VOLUMK XXIV. 
BOSTON, OCTOBER, 1890. 
Number io. 
CONTENTS. 
Familiar Science. — Scientific Recreations . 145 
Some Ancient Chemical Symbols .... 145 
A Curious Tree 146 
With the Microscopes at Detroit .... 146 
IJotanical Notes from the Region of New 
Mexico 147 
A Few Rhode Island Orchids 148 
Autographism 148 
Ballhatchet— Bailhache 148 
The Chigger 148 
Practical Chemistry and the Arts. — The 
Manufacture of Sodic Carbonate . . . 149 
The Ores of Iron 149 
Steel Railway Ties 150 
Industrial Memoranda 150 
The Out-Door World. — On the Shores of 
Lake Qiiinsigamond 150 
The Romance of Chapter 187 151 
Chapter Addresses, New and Revised . . 151 
Original Observations 151 
About Grasses 152 
Editorial. — Gold 153 
Indiana's, Welcome to the American Ass'n 154 
Paris Letter 155 
Meteorology for August, 1S90, With Review 
of the Summer 156 
Astronomical Phenomena for October, 1890 157 
Literary Notes 157 
Medicine and Pharmacy. -^Photography for 
Physicians IJ7 
The Medico-Legal Examination of Blood 
and Blood-Stains 158 
The Tenth International Medical Congress 159 
Monthly Summary of Medical Progress . . . 160 
Publishers' Column 160 
Banjiliar ScieQce. 
SCIENTIFIC RECREATIONS. 
A si.MPi.E miniature filter, illustrating both 
the purifying power of charcoal and the prin- 
ciple of the siphon, can be made by taking a 
charcoal, closely packed in the powder of the 
same substance. A piece of muslin may be 
tied over the bowl to prevent the charcoal 
from becoming displaced, and a bit of cotton 
wool in the bottom of the bowl will prevent 
the dust froiTi entering the stem of the pipe. 
Attach a piece of rubber tubing to the pipe, 
and, having previously filled it with water, 
place the apparatus in a vessel of water, as 
shown in the engraving. The rubber tube 
must be long enough to reach below the 
bottom of the vessel containing the water. 
Under these conditions the water will slowly 
pass through the apparatus, being more or 
less purified by the charcoal in so doing, and, 
flowing through the rubber tube, fall into a 
vessel placed, to receive it. The flow may be 
conveniently stopped at any time by compress- 
ing the tube with a pinchcock, which may be 
easily made from a stout hairpin bent into the 
form ABC. One of these filters in constant 
operation will supply water enough for several 
persons, but their value is more scientific than 
practical. 
An ingenious French toy is the electro- 
magnetic top, which is, in etlect, a miniature 
dynamo machine. The interior is divided 
into two parts, only one of which rotates 
when the top is spinning. In one compart- 
ment are placed three small magnets, as 
shown in 2. In the lower compartment (i) 
are three little coils of fine wire connected 
together. These are connected to a toothed 
clay jiipe of the largest size and filling the 
bowl with small fragments of freshly-burned 
wheel (3), which acts as a ciicuit breaker. 
In the act of spinning the top, the axis is 
supported by a handle, around which is 
wound a string, which is pulled by the other 
hand (see engraving). The connections are 
.so arranged that when the top rotates, the 
current of electricity passes through this 
handle and into the hand of the person spin- 
ning the top, giving him quite a perceptible 
shock, much to his surprise and mystification. 
Probably the current produced by such an 
apparatus would be sufficiently powerful to 
admit of other and even more surprising 
manifestations. 
The accompanying engravings are repro- 
duced from La Nature. 
SOME ANCIENT CHEMICAL 
SYMBOLS. 
We give below a reproduction (from Meyer 
Bros.' Druggist) of some chemical and 
pharmaceutical symbols used by the mcdi- 
ajval alchemists in their mystical, and often 
nonsensical writings. Each separate charac- 
ter on the same horizontal line is a symbol 
of the same substance, the names of which 
are given below. 
««<■, ooo<,5oooe> 
(0, Sis, %S&..o<, 9S.tf'P. • 
Atbunien 
Alcohol 
Alkali 
Alum 
Arsenic 
Borax 
Camphor 
Drachm 
Gold 
Gum 
Money 
Iron 
The character for drachm., it will be no- 
ticed, is still in use, but the other symbols 
have long since been given up and the simpler 
forms of letters and figures substituted. These 
modern chemical symbols are in themselves 
only much-condensed abbreviations, and indi- 
cate to the eye of the chemist, facts in regard 
to the properties and relations of the sub- 
stances they represent, that, if written out in 
full, would cover many pages of text. The 
modern tendency in naming new substances 
is also in this direction, so that even such a 
polysyllabic atrocity as methylenehexphenyl- 
phosphonium iodide indicates most clearly 
