RECORDS. ei 
by some one not entirely familiar with the subject, it not infrequently happens that 
the statements in the paper which have been omitted from the abstract as unim- 
portant prove in the end to be the essential ones so far as the owner of the abstract 
is concerned. For this reason, when they are within reach, the writer prefers to 
consult the original papers and to save for original work the time consumed in 
making long abstracts. When they are rare, frequently needed, and only to be had 
by borrowing, the writer has sometimes 
photographed the more essential parts. 
In one instance a pamphlet was bor- 
rowed from Europe for this purpose. 
For the exact measurement of col- 
onies, etc., a strip of plate glass 35 cm. 
long and ruled into 350 mm. spaces 
may be had from Carl Zeiss, and will 
be found very convenient (fig. 102). 
Steel rules of any size and of very 
excellent workmanship, graduated ac- 
cording to the English or the metric 
system in any degree of fineness, may 
be had from the L,. S. Starrett Com- 
pany, Athol, Mass. ‘Two of these rules 
much used by the writer are, respec- 
tively, 12 inches and 30 centimeters 
long. They are one inch wide and 
about three sixty-fourths of an inch 
thick. ‘They are graduated on both 
sides, the metric rule into centimeters, 
millimeters, and one-half millimeters, 
and the English into inches, halves, 
quarters, eighths, sixteenths, thirty- 
seconds, and sixty-fourths. 
Stage micrometers made by Zeiss 
are recommended for the finer measure- 
ments. ‘These have 1 millimeter 
divided into tenths, twentieths, and 
Fig. 102.* one-hundredths very accurately. All 
: the magnifications of microscopic 
objects figured in this book are recorded in terms of such a micrometer. After the 
drawing has been made it is customary to substitute for the section-slide this stage 
micrometer and throw the image of some portion of the ruled scale on the paper 
*Fic. 102,—Green cucumber soft-rotted by Bacillus aroideae. Contents emptied out and skin 
filled with water and so photographed, 3 days from date of inoculation, which was by means of a 
few needle-pricks. The fruit was kept at about 25° C. The black bands are pencil marks on the 
millimeter rule placed inside. The numerous small dark spots are denser bits of tissue which did 
not wash free on rinsing out the sack with water. At the left drops of water may be seen oozing 
through the skin and falling. Photograph, nearly natural size, by Townsend. 
