—This portion of the American continent is notoriously unhealthy, especially along the only routes practicable for an inter-oceanic canal.

It is said that the construction of the railway across Panama cost a human life for every sleeper that was laid.

Much of this is due to malaria, but yellow fever also frequently attacked the workers, and it is to be hoped that as both these diseases are known to be capable of transmission only by the agency of mosquitoes, that a rational prophylaxis against the bites of these insects will form part of the sanitary programme of the huge work that is now being proceeded with. In any case, when the new canal comes to be finished it will behove passengers by the mail boats to provide themselves with mosquito nets for this portion of the voyage.

Rainfall Table of Mexican Stations.
PlacePacific
Coast
Central PlateauAtlantic Coast
MazatlanChihuahuaLeonMexicoOxacaMatamorosVera Cruz
Latitude,
N.
23° 11′28° 38′21° 7′19° 26′16° 57′25° 49′19° 12′
Longitude,
W.
106° 24′106° 30′101° 40′99° 8′94° 42′97° 38′96° 8′
Elevation30 ft.4,650 ft.5,850 ft.7,400 ft.5,150 ft.63 ft.48 ft.
ScaleIns.Mm.Ins.Mm.Ins.Mm.Ins.Mm.Ins.Mm.Ins.Mm.Ins.Mm.
January1·34341·49380·3690·1640·1331·58400·3910
February0·2460·2870·3480·2460·55142·34590·5514
March0·2460·000·3690·59150·59152·44620·6018
April0·0410·2460·2870·59151·77452·24570·133
May0·2871·38351·14292·02513·941002·22564·26108
June1·85478·512164·881244·091048·642193·639212·48317
July6·541666·041535·681444·091044·091042·376014·81376
August10·352575·241335·911504·831234·261081·66428·74222
September8·632191·08275·071293·971015·941517·0417911·62295
October3·15801·14291·69431·68432·92744·451139·03229
November0·48120·000·39100·43110·39104·471143·2482
December0·91230·0820·3690·1640·0312·24572·0351
Year33·9286325·4464626·3967122·9758133·2184436·6693167·921,728

The north-east Trades dominate the Atlantic coast of these regions throughout the year, but on the Pacific side, during the summer months, a southerly breeze takes its place.

The rainfall is very heavy, but even here, in spite of the narrowness of the dividing belt of land, the comparative dryness of the Southern or Pacific coast is quite obvious, as may be seen from a glance at the [table] on the following page.

The rainfall, it will be noted, varies greatly owing to small local differences of environment, and includes at least one place far up on the world’s list of the wettest spots.

The stifling heat and damp of Greytown used to be well known to naval officers of the last generation, and it is probably a fortunate circumstance for their successors that the harbour has now so silted up as to be useless, for at one time it was frequently visited by our men-of-war.

The corresponding temperature records, given below, do not run very high, but the places on the Atlantic shore are extremely enervating on account of the extreme dampness of the air.

Table of Temperatures in Localities in Central America.
PlaceAbsolute
Mean
Annual
Maxima
Absolute
Mean
Annual
Minima
Coldest MonthWarmest Month
NameMean
Temperature
NameMean
Temperature
F.C.F.C.F.C.F.C.
San Salvador93·434·156  13·3December70·221·2April75·224  
Taboga Island96·535·866·419·1February77·225·1June80·226·8
San José88·531·450·210·1December65·618·7May68·720·4
Coban88·331·340·24·5December62·316·8May68·820·5
Guatemala87·530·845·67·6January62·016·7May68·520·3
Quezaltenango76·424·626·7-3·0January50·210·1May62·016·7
Belize91·232·959·615·4December74·523·6August82·528·1
Colon94·334·566·018·9November78·525·8June79·826·6
Gamboa96·635·957·214·0February76·824·9June80·426·8