JANUARY 18, 188+4.] 
per light is 133 feet above high water, its nautical 
‘range is 174 miles, and in clear weather it overlaps 
the beam of the electric lights from the Lizard Point. 
The lantern is of the cylindrical helically-framed 
type adopted by the Trinity House. The light is de- 
rived from two six-wick ‘ Douglass’ burners, the illu- 
minant being colza-oil. With aclear atmosphere, and 
the light of the Plymouth breakwater lighthouse (10 
miles distant) distinctly visible, the lower burner only 
is worked at its minimum intensity of 450 candles, 
giving an intensity of the flashes of the optical ap- 
paratus of 37,800 candles; but, whenever the atmos- 
phere is so thick as to impair the visibility of the 
breakwater-light, the full power of two burners is 
put in action, with the aggregate intensity of 1,900 
candles for the lamps, and an intensity of the optical 
apparatus of 159,600 candles. This intensity is 
about 23.3 times greater than that of the fixed light 
latterly exhibited from Smeaton’s tower, and about 
3,282 times that of the light first exhibited in the 
tower from tallow candles. The new tower was built 
at a distance of 130 feet from Smeaton’s lighthouse, 
a large portion of the foundation being laid below the 
level of low-water spring-tides. The estimate for the 
work was £78,000, and the cost £59,255. The first 
landing at the rock was made in July, 1878, and the 
work was carried on until December. Around the 
foundation of the base of the tower a strong coffer- 
dam of brick and Roman cement was built for getting 
in the foundations. By June, 1879, the work was 
sufficiently advanced for the stones to be laid in 
the lower courses, and every thing was arranged for 
H.R.H. the Duke of Edinburgh to lay the foundation- 
stone on the 12th of the month; but, the weather be- 
ing stormy, the ceremony was postponed until the 19th 
of August. On the 17th of July, 1880, the cylindrical 
pase was completed, and the 38th course by the early 
part of November. On the Ist of June, 1881, the 
Duke of Edinburgh, when passing up the Channel in 
H.M.S. Lively, landed at the rock, and laid the last 
stone of the tower. On the 18th of May, 1882, the 
Duke of Edinburgh completed the work by lighting the 
lamps and formally opening the lighthouse. The edi- 
fice was thus erected and fitted up within four years 
of its commenc-ment, and one year under the time 
estimated. The whole of the stones, averaging more 
than 2 tons each, were landed and hoisted direct into 
the work from the deck of the steam-tender Hercu- 
les, by a chain-fall working between an iron crane 
fixed at the centre of the tower, and a steam-winch on 
the deck of the Hercules, which was moored at a 
distance of 30 fathoms from the rock. 
The town council and inhabitants of Plymouth 
having expressed a desire that Smeaton’s lighthouse 
should be re-erected on Plymouth Hoe, in lieu of the 
Trinity House sea-mark thereat, the Trinity House 
made over to the authorities at Plymouth the lantern 
and four rooms of the tower. After the removal of 
the structure to the floor of the lower room, the en- 
trance-doorway, and well-staircase leading from it to 
the lower room, were filled in with masonry, and an 
iron mast was fixed at the centre of the top of the 
frustum. 
SCIENCE. 83 
— The U.S. naval institute offers a prize of a gold 
medal, one hundred dollars, and a life membership, 
to the writer of the best essay offered on the subject 
of ‘The best method for the reconstruction and in- 
crease of the’navy.’ The judges selected to adjudge 
the prize are Dr. D. C. Gilman, Admiral C. R. P. 
Rodgers, Senator J. R. Hawley. 
—E. & F. N. Spon announce the publication at 
an early date of a book on ‘Sorghum, its culture 
and manufacture economically considered,’ by Peter 
Collier; also ‘ Electricity, magnetisin, and electro- 
telegraphy,’ by D. T. Lockwood. 
— Professor Gustavus Hinrichs, director of the 
Iowa weather-service, has again issued an attractive 
annual pamphlet, entitled this year ‘The seasons in 
Iowa, and a calendar for 1884,’ with appropriate illus- 
trations, and much valuable meteorological informa- 
tion. The notable weather features of the several 
months are given in detail; so that observers may 
judge at any time whether an occurrence is normal 
and probably to be continued, or abnormal and likely 
soon to disappear. ‘The chief peculiarity of the cli- 
mate is its variability, common to interior stations on 
the track of frequent cyclonic storms, and of which 
several striking examples are given; and there is 
found to be much probability of a cold snap late in 
January, a snow-storm at the close of April, a cold 
spell in May, tornadoes in June, squalls in July, heavy 
local rains in August, and frost early in September. 
Since 1875, tornadoes have occurred in Iowa on the 
following dates: April 8, 18, 21, 23; May 9, 13, 18, 
19; June 1, 4, 9, 11, 12, 14, 17, 24; July 2; Oct. 8, 
15, 28, 380 (the more severe ones in bold type). June 
is the month most disturbed by these storms; and 
directly after it a three-month period, July 3 to Oct. 8, 
has no record of tornadoes. It is said that the dan- 
ger from tornadoes in Iowa has been greatly exag- 
gerated. The rainfall maps for every month and for 
the year are repeated from last year. Precipitation 
is almost three times as great in summer as in winter. 
Professor Hinrichs hopes next year to illustrate his 
annual from home sources exclusively, and asks for 
sketches and photographs of halos, hail stones, de- 
structive effect of wind and lightning, meteors, cloud- 
forms, or any other phenomena. Drawings of Iowa 
scenery, as well as detailed maps of storms, hail, and 
floods, will all be welcome. We wish the director 
success in his excellent work. 
— The publications of the census office so long ex- 
pected are now being issued in rapid succession by the 
Government printing-office. .Thus far, three quarto 
volumes, besides the compendium, have appeared, and 
several others are very near completion. The three 
which have been issued are those upon population, 
manufactures, and agriculture. The first, which saw 
the light some two months ago, comprises ‘ Popula- 
tion, part 1,’ as issued by the census office a year and 
a half ago, with, as additions, the tables relating to 
race, nativity, age, sex, parentage, Occupations, il- 
literacy, the defective, dependent, and delinquent 
classes, and the newspaper and periodical press. The 
tabular matter is preceded by a somewhat full discus- 
